evolution: rename trouble(s) to instability
Rename trouble(s) to instability in all external user-facing output. Only
update user-facing output for the moment, variables names, templates keyword
and potentially configuration would be done in later series.
The renaming is done according to
https://www.mercurial-scm.org/wiki/CEDVocabulary.
Differential Revision: https://phab.mercurial-scm.org/D213
$ echo "[extensions]" >> $HGRCPATH
$ echo "mq=" >> $HGRCPATH
$ hg init
$ echo 'base' > base
$ hg ci -Ambase
adding base
$ hg qnew -mmqbase mqbase
$ hg qsave
$ hg qrestore 2
restoring status: hg patches saved state