bug 6812: pedigree view is broken in RTL locales

Make the table widget in the view forced LTR.
Everything else (person box widget and the top window) is
LTR or RTL, depending on the locale.
Unfortunately, due to current broken pango logic,
for RTL locales the person boxes will still be left-aligned :-(

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/branches/maintenance/gramps34@22521 4ae1f11a-8b86-4847-b8af-ab372f36d1fd