bundle-spec: properly parse boolean configuration as boolean
Before this changesets "v2;revbranchcache=no" would actually request the
addition for a revbranchcache part as the non-empty string `"0"` is `True`
https://bz.mercurial-scm.org/842
$ hg init repo
$ cd repo
$ echo foo > a
$ hg ci -Ama
adding a
$ hg up -r0000
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo bar > a
Should issue new head warning:
$ hg ci -Amb
adding a
created new head
$ hg up -r0000
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo stuffy > a
Should not issue new head warning:
$ hg ci -q -Amc
$ hg up -r0000
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo crap > a
$ hg branch testing
marked working directory as branch testing
(branches are permanent and global, did you want a bookmark?)
Should not issue warning:
$ hg ci -q -Amd