tests: run check-code with warnings and maintain a whitelist
check-code has fine warning checks, but they are a bit noisy and nobody used
them.
Now the warnings will be run in the test suite, where a list of accepted
warnings will be maintained.
Those who introduce or touch a line with a warning will now have to update the
whitelist ... or fix the warning.
http://mercurial.selenic.com/bts/issue1089
$ hg init
$ mkdir a
$ echo a > a/b
$ hg ci -Am m
adding a/b
$ hg rm a
removing a/b (glob)
$ hg ci -m m a
$ mkdir a b
$ echo a > a/b
$ hg ci -Am m
adding a/b
$ hg rm a
removing a/b (glob)
$ cd b
Relative delete:
$ hg ci -m m ../a