Error while upgrading from Debian 7 to 8

First of all, I am 100% certain that this error is my own fault (I've fixed every other issue I've had before) as I extremely foolishly somehow quit the ssh session which was performing dist-upgrade. Here's the current situation:

[email protected]:/home/alex# apt-get dist-upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt-get -f install' to correct these.
The following packages have unmet dependencies:
 consolekit : Breaks: udev (< 204-1) but 175-7.2 is installed
E: Unmet dependencies. Try using -f.
[email protected]:/home/alex# apt-get -f install
Reading package lists... Done
Building dependency tree
Reading state information... Done
Correcting dependencies... Done
The following packages were automatically installed and are no longer required:
  alsa-utils libdrm-nouveau1a libmowgli2 libmozjs10d libmpc2 libproxy0 python-gnupginterface python-pycurl
Use 'apt-get autoremove' to remove them.
The following extra packages will be installed:
  udev
The following packages will be upgraded:
  udev
1 upgraded, 0 newly installed, 0 to remove and 490 not upgraded.
Need to get 0 B/875 kB of archives.
After this operation, 5,211 kB of additional disk space will be used.
Do you want to continue [Y/n]?
Preconfiguring packages ...
(Reading database ... 71396 files and directories currently installed.)
Preparing to replace udev 175-7.2 (using .../udev_215-17+deb8u1_amd64.deb) ...
Since release 198, udev requires support for the following features in
the running kernel:
- inotify(2)            (CONFIG_INOTIFY_USER)
- signalfd(2)           (CONFIG_SIGNALFD)
- accept4(2)
- open_by_handle_at(2)  (CONFIG_FHANDLE)
- timerfd_create(2)     (CONFIG_TIMERFD)
- epoll_create(2)       (CONFIG_EPOLL)
Please upgrade your kernel before or while upgrading udev.
AT YOUR OWN RISK, you can force the installation of this version of udev
WHICH DOES NOT WORK WITH YOUR RUNNING KERNEL AND WILL BREAK YOUR SYSTEM
AT THE NEXT REBOOT by creating the /etc/udev/kernel-upgrade file.
There is always a safer way to upgrade, do not try this unless you
understand what you are doing!
dpkg: error processing /var/cache/apt/archives/udev_215-17+deb8u1_amd64.deb (--unpack):
 subprocess new pre-installation script returned error exit status 1
Errors were encountered while processing:
 /var/cache/apt/archives/udev_215-17+deb8u1_amd64.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
[email protected]:/home/alex#
[email protected]:/home/alex# cat /etc/issue
Debian GNU/Linux 7.1
Linux xxx 3.10.9-xxxx-grs-ipv6-64 #1 SMP Wed Aug 21 11:51:59 CEST 2013 x86_64 GNU/Linux
[email protected]:/home/alex# cat /etc/debian_version
8.1

I tried dpkg --configure -a before doing apt-get -f install but with no success. Any idea how to fix this problem?

you need to upgrade your kernel first

How do I go about doing that?

[email protected]:/home/alex# apt-cache search linux-image
linux-headers-3.2.0-4-amd64 - Header files for Linux 3.2.0-4-amd64
linux-headers-3.2.0-4-rt-amd64 - Header files for Linux 3.2.0-4-rt-amd64
linux-image-3.2.0-4-amd64 - Linux 3.2 for 64-bit PCs
linux-image-3.2.0-4-amd64-dbg - Debugging symbols for Linux 3.2.0-4-amd64
linux-image-3.2.0-4-rt-amd64 - Linux 3.2 for 64-bit PCs, PREEMPT_RT
linux-image-3.2.0-4-rt-amd64-dbg - Debugging symbols for Linux 3.2.0-4-rt-amd64
linux-image-2.6-amd64 - Linux for 64-bit PCs (dummy package)
linux-image-rt-amd64 - Linux for 64-bit PCs (meta-package), PREEMPT_RT
linux-headers-3.16.0-4-amd64 - Header files for Linux 3.16.0-4-amd64
linux-image-3.16.0-4-amd64 - Linux 3.16 for 64-bit PCs
linux-image-3.16.0-4-amd64-dbg - Debugging symbols for Linux 3.16.0-4-amd64
linux-image-amd64 - Linux for 64-bit PCs (meta-package)
linux-image-amd64-dbg - Debugging symbols for Linux amd64 configuration (meta-package)
nvidia-kernel-3.16.0-4-amd64 - NVIDIA binary kernel module for Linux 3.16.0-4-amd64

try the linux-image-3.16.0-4-amd64 one

[email protected]:/home/alex# apt-get install linux-image-3.16.0-4-amd64
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
 consolekit : Breaks: udev (< 204-1) but 175-7.2 is to be installed
 linux-image-3.16.0-4-amd64 : Depends: linux-base (>= 3~) but it is not going to be installed
                              Recommends: firmware-linux-free (>= 3~) but it is not going to be installed
                              Breaks: initramfs-tools (< 0.110~) but 0.109.1 is to be installed
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

apt-get -f install doesn't solve it, as I then get the same error as in post 1.

backup what you have and do a fresh install of Debian 8.

If its not a critical system a fresh install of Debian 8 might be good, stopping updates halfway through sometimes breaks things.

On another note why is udev being installed.. isnt systemd the default in Debian 8?

It's not a critical system but I do not have physical access to it and my home connection is too crappy to have patience to backup all the data from it. Would prefer if it was possible to fix it with some kind of bodgejob, but if not then I just have to backup the most important config files and install it from scratch. It primarily acts as a remote backup as well as running a handful of services for me.

With regards to udev I have no idea. To my highly limited understanding the systems seems to be in an obscure state where it's not sure whether it's upgraded or not.