Extracts check for 256 colors
Adds #highlight to Colors
Adds code block formatting to Formatter
Adds inline code formatting in Formatter
Fixes indentation of code block surrounders
Uses indentation to delimit code blocks
Improves backwards compatibility

... by using the old hash style in Pygmentizer.
Uses GHI.config in Pygmentizer

... instead of a plain environmental variable.
Adds info about Syntax Highlighting to the README
Fixes minor issue in code block regex

Fenced code blocks can include spaces between the backticks and the
language hint.
Merge pull request #150 from LFDM/syntax_highlighting

Syntax highlighting