preferences file within LyX.app bundle
* MacOSX/LyX.app/Contents/Resources/preferences: update
path_prefix to include /opt/local/bin, and remove references to
"-1.4" version suffix
git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/branches/BRANCH_1_4_X@13480 a592a061-630c-0410-9148-cb99ea01b6c8