Add an option to not test in repo mode

Summary: The repo tests sometimes hang for me or take a unreasonable amount of time.
Add an option to skip them. Default is still to test it though.
Closes https://github.com/facebook/hhvm/pull/3858

Reviewed By: @ptarjan

Differential Revision: D1580850
Fix a bug in castBoolImpl for arrays

Summary: Pretty bad bug.  It was ignoring the 'negate' arg.

Reviewed By: @bertmaher, @swtaarrs

Differential Revision: D1580833
Remove unused m_shouldCache bool in APCHandle

Summary: Nothing reads it, except to set it elsewhere.

Reviewed By: @alexmalyshev

Differential Revision: D1571331
Tweak headers so changing concurrent-shared-store.h doesn't rebuild world

Reviewed By: @alexmalyshev

Differential Revision: D1573497
Some clean up in APCHandle

Summary: - Move DataWalker to its own file

    - Add apc-typed-value.cpp and move some member function definitions there

    - Remove some unused or redundant functions

    - Normalize some naming (getFoo vs isFoo)

    - Renamed isObj (it really meant isNotSerializedObj) and inverted it so it
      parallels isSerializedArray.

    - Fix data race in setObjAttempted

    - Document thread-safety rules and add some consts accordingly

Reviewed By: @alexmalyshev

Differential Revision: D1574091
Removed unused includes and types from ir.h

Summary: Things were depending on translator-runtime.h indirectly. Bleh.

Reviewed By: @bertmaher

Differential Revision: D1579882
Add short form option for help command

Summary: It is quit common to use -h option for cli command
Closes https://github.com/facebook/hhvm/pull/3803

Reviewed By: @ptarjan

Differential Revision: D1568492
ReflectionClass::getStaticPropertyValue throws exception if not found & ...

Summary: ...no default value given

This is ugly, but I see no other way.

Fixes #3841

Closes https://github.com/facebook/hhvm/pull/3851

Reviewed By: @ptarjan

Differential Revision: D1578221