Merge branch 'nd/help-commands-verbose-by-default'

"git help -a" and "git help -av" give different pieces of information, and generally the "verbose" version is more friendly to the new users. "git help -a" by default now uses the more verbose output (with "--no-verbose", you can go back to the original). Also "git help -av" now lists aliases and external commands, which it did not used to. * nd/help-commands-verbose-by-default: help -a: improve and make --verbose default