Issue 313 & 314 - Add package access to rt.lifetime.BlkInfo

Supplemental fix for these compiler bugs.
[Issue 313](http://d.puremagic.com/issues/show_bug.cgi?id=313) - [module] Fully qualified names bypass private imports
[Issue 314](http://d.puremagic.com/issues/show_bug.cgi?id=314) - [module] Static, renamed, and selective imports are always public

`rt.lifetime.BlkInfo` is used from `rt.tlsgc`, so at least it should have `package` access.