Verified changes to ensure fixes #296.
require('codemirror/mode/css/css');
require('codemirror/mode/clike/clike');
+require('codemirror/mode/diff/diff');
require('codemirror/mode/go/go');
require('codemirror/mode/htmlmixed/htmlmixed');
require('codemirror/mode/javascript/javascript');
'c++': 'clike',
'c#': 'clike',
csharp: 'clike',
+ diff: 'diff',
go: 'go',
html: 'htmlmixed',
javascript: 'javascript',
ruby: 'ruby',
rb: 'ruby',
shell: 'shell',
+ sh: 'shell',
bash: 'shell',
toml: 'toml',
sql: 'sql',