Fixed dependency order when uninstalling packages

In PETget package manager, sometimes just called the "PPM", I had introduced dependency checking when uninstalling user-installed packages. Wow, that was back in 2013, for Quirky Linux -- and there has been a bug since then.

The bug was that the checking logic was reversed. For example, I have installed 'blockout2', which has dependencies 'libmikmod3' and 'libsdl-mixer1.2'. Before I fixed it, if I tried to uninstall 'blockout2', the PPM refused, saying that there are installed packages that require it. On the otherhand, if I clicked to uninstall 'libmikmod3', it succeeded.

That bug had been written down a few time on various to-do lists, but I never got around to it. Today I decided that 6 years is long enough for that bug to exist, time for it's demise. Now fixed. 

One nice feature, that was introduced in 2013, is if I remove 'blockout2', the PPM will inform me that 'libmikmod3' and 'libsdl-mixer1.2' are not required by any other packages and can be removed if I wish.  That is working OK. 

Tags: easy