Upgrade to 3.5.0 release.

USES=python

Give the port a chance of building on more arm systems and powerpc64. [0]

Allow building on 9 in the default configuration as it works for me.
Disallow llvm35 on 8 due to bizzare gcc behavior.

PR: 191996 [0]
Submitted by: direct727@gmail.com [0]
Sponsored by: DARPA, AFRL