Support for %HOME% added if declared

OpenSSH and Git uses the folder defined in the HOME Environment Variable, if declared, instead of ~\. Now also Poshgit support these.

See http://www.google.de/#hl=de&tbo=d&sclient=psy-ab&q=git+home+environment+variable&oq=git+home+&gs_l=serp.1.2.0l4.2145.4026.0.6454.6.5.0.1.1.1.499.1124.2j1j0j1j1.5.0...0.0...1c.1.KAWfBJOlIN8&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.&fp=56a43b64ebecf8e3&biw=1600&bih=805