Fix some Arcanist lint warnings

Summary: Lint. See https://github.com/facebook/phabricator/pull/332

Test Plan: Lint.

Reviewers: chad

Reviewed By: chad

CC: aran

Differential Revision: https://secure.phabricator.com/D6126
Verify classes used in typehints

Summary: Also support `SomeInterface::CONSTANT`.

Test Plan:
  interface I {
    const A = 1;
  }
  I::A;

  function f(stdClass $a, array $b, Iterator $c) {
  }

Linted Phabricator.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D6135
Find classes used in call_user_func()

Summary:
Also fix false positive for call_user_func('C::f').
Also fix false positive for call_user_func("$f").
Also centralize handling of magic classes.

Test Plan:
  call_user_func("$f");
  call_user_func('C::f');
  call_user_func(array('C', 'f'));
  call_user_func(array(1 => 'f', 0 => 'C'));

Linted Phabricator.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D6137
Find needed classes in catch, instanceof and newv()

Test Plan:
  try {} catch (X $ex) {}
  $a instanceof X;
  newv('X');

Linted Phabricator.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D6143
Merge branch 'master' of http://github.com/facebook/arcanist