i18n-ja: synchronized with 69ffbbe73dd0

tag: clarify warning about making a tag on a branch head Currently the warning is ambiguous about whether the new tag (possibly specified via --rev) is being added on a branch head or whether the working directory is based on a branch head. Clarify the error message to eliminate this ambiguity.

contrib: check reference to old selenic.com domain Now, all URL in Mercurial source tree should refer mercurial-scm.org domain instead of selenic.com. *.po files are ignored in this patch, because they might contain msgid/msgstr coming from old source files. This ignorance seems safe enough, because such msgstr should be ignored at runtime, because: - msgid corresponded to it should be invalid, or - msgstr itself should be marked as fuzzy at synchronized to recent hg.pot If any additional examination for *.po files is needed in the future, let i18n/check-translation.py achieve such examination. BTW, some binary files (e.g. *.png) are meaningless for checking reference to old domain in this patch, but aren't ignored like as *.po files, because excluding multiple suffixes is difficult for regexp matching.