minirst: use colwidth to match title lengths (issue2455)

encoding: default ambiguous character to narrow The current implementation of colwidth was treating 'A'mbiguous characters as wide, which was incorrect in a non-East Asian context. As per http://unicode.org/reports/tr11/#Recommendations, we should instead default to 'narrow' if we don't know better. As character width is dependent on the particular font used and we have no idea what fonts are in use, this recommendation applies. This introduces HGENCODINGAMBIGUOUS to get the old behavior back.

*: kill all unnecessary shebangs.

*: add executable bit to a few files that were missing it.

log: do case insensitive search for --user option

url: show realm/user when asking for username/password

rebase: abort message should appear even with --quiet

help: correct tip about deleting a subrepository The extra detail is not necessary, and wrong for Mercurial subrepositories, so remove it (suggested by Patrick Mézard).

revset: fix missing dot in docstring

help: fix typo in merge-tools topic