highlight: clean up coding style a little

extension for synax highlighting in the hgweb file revision view Depends on the pygments syntax highlighting library: http://pygments.org/

Change standard streams mode to binary at hg startup Standard streams are expected to operate in binary mode everywhere, especially with archive, cat, diff and export commands. Rewriting these to separate informational output from binary content is complicated to do and to maintain, nonwithstanding mode switching reliability. Changing all output mode to binary should not have much impact on Windows were stream processing tools are barely used and usually cope with unix style endings. Streams mode being process wide, the switch is performed in the startup script to avoid polluting existing API users who may have solved this issue already or ignored it at least for the mercurial part.