hg status: added options to select files by status. Added options -m, -a, -r and u to select files corresponding to status M, A, R and ? respectively. If none of these options are specified, files of all status will be shown.

+ hg init
+ hg add a
+ hg commit -m test -d 0 0
precommit hook
commit hook: acb14030fe0a21b60322c440ad2d20cf7685a376