Now the framework works running LyX in the language required by the test

Now the framework works running LyX in the language required by the test
script (if any) also when LyX is not installed on your system
(using a variant of the trick suggested by Enrico, i.e., create a symlink
locale from the LyX sources root to an autotests/locale folder).
At least, it does on Linux.

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@37589 a592a061-630c-0410-9148-cb99ea01b6c8