Notable changes:
* Added new token types and lexing for magic methods and variables in
Python and PHP.
* Added a new token type for heredoc (and similar) string delimiters and
lexing for them in C++, Perl, PHP, Postgresql and Ruby lexers.
* Improved the CSS lexer.
* Added Varnish config lexer
Full changelog is found at:
<bc45808f83/CHANGES>
Bug: T156573
Change-Id: I4dc1782f19881ba1294308e1cdea1b2e063f438a