Combine string token followed by reference

[simshaun]

Closes #780

[theofidry]

👌

Do you mind to add a small integration test? You'll need to add it in both LexerIntegrationTest and ParserIntegrationTest as both need to be synchronized

[simshaun]

Added integration tests. I wasn't exactly sure what to name the scenarios or where to place them in the data provider though.

[simshaun]

Not sure why the lexer test is failing in the Symfony run on Travis.

[theofidry]

This indeed looks very weird, can you reproduce it locally (try make ts)? I'll try to check it out during the week

[simshaun]

Yea I just got it to error locally with make ts. I'm trying to figure out why the Symfony test lexes differently, but I'm stumped at the moment.

Edit: Think I got it. The new lexer needed to be setup in the lexer chain in the Symfony DIC.