Add Code Model support for "require extends class" and "require implements interface" statements.

Added templates for two new statement types. Added serialization support. Added references to these types to the generator scripts.

Reviewed By: @elgenie

Differential Revision: D1118441
Move frameworks to master or develop branches

Move all the frameworks away from just specific git hashes to a master, develop (or equivalent) branch.

We start off with specific git hashes for the branch, but now there is a --latest and --reset option that gets the latest source for that branch and updates our new frameworks.json file with the latest hash.

I will do a --reset after this diff is approved to get new .expect files, etc.

Reviewed By: @ptarjan

Differential Revision: D1099135
Remove Array::lval since it basically duplicates Array::lvalAt

Array::lval is almost identical; it just requires that
AccessFlags::Key be passed where string-integer keys can be created
(e.g., dynamic object properties).

Reviewed By: @markw65

Differential Revision: D1121403
Miscellaneous cleanup of Array

This is basically just moving things around to make the API
more obvious and conform to our general coding style.

Reviewed By: @edwinsmith

Differential Revision: D1121410
vm_decode_function doesn't verify parent has __call[Static]

When running call_user_func(array('C', 'parent::doesntExist')), Zend
runs C::__call if it exists and if the parent of C also has a
__call method. We were just checking C.

Closes #1471

Reviewed By: @ptarjan

Differential Revision: D1121885
Fix the build with the newer versions of libdwarf

This fixes an error with inconsistent types being used for the 'name'
parameter when registering a libdwarf callback against newer versions
of libdwarf (versions where the 'name' parameter is a const char*).

I verified that this compiles with the latest version of libdwarf.

Closes #1525

Reviewed By: @alexmalyshev

Differential Revision: D1122805

Pulled By: @scannell
Use pkg-config to find freetype2 and clean up cmake module

This was doing clowny things including looking for a
header that we're not interested in using.

Closes #1380