Extract source parsing logic to SourceParser
Transfer responsibility of handling syntax offences to CLI
Refactor SourceParser#parse
Refactor SourceParser#disabled_lines_in and improve performance
Invoke cops' custom callback before processing the AST

This allow the cop to obtain additional information or reference
from source_buffer, comments and tokens before we start processing
the AST.
Merge pull request #363 from edzhelyov/call-cops-callbacks-before-ast

Invoke cops' custom callback before processing the AST
Merge pull request #359 from yujinakayama/source-parser

Extract source parsing logic to SourceParser
Allow safe assignment in ParenthesesAroundCondition (fixes #356)
Fix incorrect example