Release 1.14.5

@thiblahute could you have a look at these changes?

I skipped large updates of the .cs files and churn in the raw/xml API files which mostly seems to be minor/unimportant changes and/or removes dllimport stuff that doesn't generated for me.

Only real change is in Gst.Video/Global.cs - the _add_meta_full().

Maybe I should just drop that and the gir updates though and just keep the version bump?