Switch to USES=python and autoplist
Allow staging as a regular user and simplify

PR:		ports/193102
Fix pkg-plist

Reported by:	antoine
Add USES=libtool and INSTALL_TARGET=install-strip
Add USES=libtool and INSTALL_TARGET=install-strip
- Drop .la files, no dependees require them

Approved by:	portmgr blanket
Convert to USES=libtool:build
Update to alpha-20140817