Remove duplicate bunidiff code from hgdiff, importing from mdiff.py instead

bash_completion: ignore hg help error messages They are usually not useful when you're completing stuff and end up cluttering the screen.

bash_completion: always use single quotes with compgen -W This avoids a bug in bash 2.05a

bash_completion: be more careful about whitespaces - use awk to parse the output of hg help. - print one completion candidate per line - print the debug commands after regular commands (this eases the shell side of the parsing) - don't print aliases that are simple abbreviations (e.g. up/update, id/identify)

Added hint to hg-ssh that you can use shell pattern matching.

_hg_status improvements in bash_completion: - Use "hg status -n" option instead of cut command. - Sort status flags accoring to "hg status --help" - Show deleted files instead of "hg remove"d for "hg remove"

bash_completion: small updates and fixes - $result in _hg_commands is not an array - use "hg status ." - update "hg cat" completion - let bash itself generate the default completion

Add new bdiff based unidiff generation.

contrib: add Chris Mason's stand-alone diff tool This uses Mercurial's diff algorithm to generate unidiffs like the traditional diff tool.

Fix rcpath for hgwebdir case (sys.argv is empty)