fixing issue #171
fixing issue #171

Fixes situation when HOME=/root and /any/other/dir/root
will be replaced with /any/other/dir~

alexprengere/liquidprompt,joshuarubin/dotfiles,dan-cleinmark/liquidprompt,mathieumd/liquidprompt,smadhueagle/liquidprompt,dtschan/liquidprompt,joshuarubin/dotfiles,milouse/liquidprompt,joshuarubin/dotfiles,nojhan/liquidprompt,illwieckz/liquidprompt,jonathanjsimon/liquidprompt,joshuarubin/dotfiles,laurentbardin/liquidprompt,enrdstrm/liquidprompt,tocomo/liquidprompt,jaesivsm/liquidprompt,tkuminecz/liquidprompt,dpilone/liquidprompt,elementalvoid/liquidprompt,tstone2077/liquidprompt,lyoshenka/liquidprompt,pkkolos/liquidprompt,timhyson/liquidprompt,tsbarnes/liquidprompt,colinlieberman/liquidprompt,BobHood/liquidprompt,kenrachynski/liquidprompt