Satisfy type checker for non-top level includes

UNSAFE no longer works for non-top level include statements.  Use the
HH_FIXME tag until it works again.
Flag classes as requiring consistent constructors when using new static
Use magic consistent construct attribute.

This tells the type checker that all children classes must have the same
signature for the constructor.

See http://docs.hhvm.com/manual/en/hack.attributes.consistentconstruct.php
for more details.
Whitespace cleanup.
Update travis config to run tests as specified in the main readme
Ensure the result time is consistent across calls.
Merge branch 'master' of https://github.com/HackPack/HackUnit
UI Text test queries the runner actual time.

the Travis test occasionally runs for 0.01 seconds.
Merge pull request #4 from kilahm/master

Update flags/comments to be consistent with current hack typechecker
Rename all files from .php to .hh