initial commit of horrendous regexp to keymap files; details of the expression are here: https://www.debuggex.com/r/uBMZ6jroTHchFMrz
horrendous regexp now supports BibLaTeX multicites
slightly improve regex by subbing {0,1} => ? and {1,} => +
add horrendous regex to cite completions
don't clobber the match() function
break-up some parts of the regex explanation
various minor fixes to the backwards regex
fix for \cites and friends
correct autocomplete for '{' TODO: make work with \volcites
Merge branch 'extended_cite_command_matching' into my_master