Summary:
This diff allows to use the linters written in DSL to check for bugs.
Now new checkers can be written directly in the DSL.
The diff also remove some weirdness and simplify the CTL semantics.
For example no need to unwrap a node when evaluating the IN operator.
Also no need to distinguish anymore between stmt and decl in the
semantics of EX and EF.
Moreover, the diff de-couple hard-coded checkers (eg checks on component kit)
from those checkers parsed in the .al files.
Reviewed By: martinoluca
Differential Revision: D4375207
fbshipit-source-id: 9ac2d47