As long as CodeMirror.normalizeKeyMap is called on them before they are
used. This interface is a little weird, but backwards-compatible.

And adjust vim mode to use these.

If "{{" was found, the code would highlight the rest of the line
regardless if a matching "}}" or "}}}" was found.

Also update the mode loading demo to make use of the info in that
file, allowing filenames and mimes to be entered.

Issue #2828

Closes #2623

Issue #2529

Issue #2494

It has been superceded by keymap/sublime.js.

The header classes for specific levels of headers, which should set the size of each header did not match the classes in the editor. This commit fixes that.