Fix issue with package reloading in Mac binary
Fix issue with package reloading in Mac binary

The issue was the fact that all packages live inside of lib/python2.7
so all included vistrails packages were identified as system packages.
Now, we just exclude anything in lib/python2.7/vistrails.

vistrails/core/modules/package.py:
  - Package.import_override.is_sys_pkg: use modified regex and logic

Ticket: 762

Nikea/VisTrails,hjanime/VisTrails,celiafish/VisTrails,VisTrails/VisTrails,Nikea/VisTrails,VisTrails/VisTrails,Nikea/VisTrails,VisTrails/VisTrails,celiafish/VisTrails,hjanime/VisTrails,minesense/VisTrails,hjanime/VisTrails,Nikea/VisTrails,celiafish/VisTrails,hjanime/VisTrails,minesense/VisTrails,hjanime/VisTrails,minesense/VisTrails,minesense/VisTrails,VisTrails/VisTrails,celiafish/VisTrails,VisTrails/VisTrails,minesense/VisTrails