[Bf-codereview] Paths and Windows Installer Fixes (issue4529081)

[brechtvanlommel at gmail.com]

I wasn't aware portable install was a feature, but it's not hard to add
back. But it needs to be implemented different, simply getting the local
path before user path breaks non-portable install. It's also not handled
this in BLI_get_user_folder_notest and BLI_get_folder_version, so e.g.
python scripts saving configuration files will not save in the right
location.

Attached a possible solution, where get_path_user returns get_path_local
if a portable install is detected (by checking for the existence of a
local config folder).

http://codereview.appspot.com/4529081/