Store cache location as relative path option.

At the moment, the cache path is stored as an absolute path... but if the usb stick that PMPC is on appears as a different drive letter, then it breaks the cache path setting stored in the PatchMyPC.ini file i've told it to create.

I want to have a disk, stick, folder with PatchMyPC.exe, PatchMyPC.ini and all the previously downloaded software, all in one flat folder... The 'current folder'.

If the cache setting could optionally be relative, then i could tell it to be the current folder and others might choose to put it in a different folder name, in a different relative location of their choosing. So it gives us ultimate flexibility.

The PatchMyPCITProCache option/folder has specific role, so that can't be used.