Switch to Meson

[ernestask]

This PR moves the build system from Autotools to Meson, with tito for release management/RPM building.

Things will be painful initially, since a lot depends on immediately tagging a release, so we can actually use tito for things (1.2.9 and earlier will not be buildable per se). The laundry list is as follows:

• Convince Jenkins to build these
• Look into writing a custom tito tagger, so that the version is meson.build is bumped as well, otherwise write a script for that
• Look into a slight refactoring to allow passing a location to the resource bundle for a slightly less annoying development workflow (even though getting an RPM will be faster than before)
• ???

Testing is as easy as following the updated README. Some caveats:

• Faking a tito tag will be necessary (poke .tito/packages/gnome-abrt and add 1.2.9-1 ./)
• The run run target is expectedly broken, but everything is mostly in place for that (had to copy all source files from srcdir to builddir, which is rather unorthodox, but ’tis Python)

[ernestask]

Eh, I should also hook pylint up.

[xsuchy]

LGTM

[ernestask]

Added a custom tito tagger. The commit messages produced are a bit unwieldy, but a lot of it is hardcoded. Don’t want to copy over the entire implementation.