big work
what was reliable before is now not, in recent versions of renpy, which is why we added that new config (which I put in say.rpy, but it can be moved somewhere else)
Also fixes the game_menu's title position, incidentally
some changes are incompatible with my diary and achievement branches, respectively, they will need to be merged with a bit of manual care
in addition to benigh simplification, this actually fixes a bug : setting pos and align in the same line is a bug, it's always been unspecified, you should have been setting *anchor* instead. xycenter does that now.
(cherry picked from commit 48c4c4ecad44402bff76e3b4dbafeeda5424b6af)
the locations of the different characters aren't independant, but they weren't in the first place
(cherry picked from commit 9a3fe1df6538977ac4f44122b64574138422f119)