Also set CodeMirror-linenumber to nowrap.

Works around issue where a rounding error causes the line
numbers to wrap in some situations on iOS.

Closes #3068

Issue #3098

So that the contenteditable input style doesn't look silly
on desktop.

It apparently believes that if the editor's nodes are directly next to
each other without margin, the user needs a magnifying glass to pick
a cursor position.

Simple things work.

Code that overrides this will break the new scroll model.

Issue #2984

And manually compensate for our own scrollbar sizes.

This way, we're no longer dependent on the size of our scrollbars
being the same as the size of native scrollbars, and can start to
think about custom scrollbars.

Also add support for "gutter" in add/removeLineClass.

Issue #2901

And adjust vim mode to use these.

Issue #2884

Issue #2765

Closes #2623

Using the CodeMirror-guttermarker and CodeMirror-guttermarker-subtle CSS
classes to give the markers their color.

Issue #2602

Also fix Erlang mode to not return a non-standard token type.

Issue #2435

This produces saner widths for most elements, and removes
the need for the border/fit-width hack on the pre elements.

Issue #2256

Conflicts:
	lib/codemirror.js

Issue #2237

(Border-sizing on the CodeMirror-linenumber class)

Issue #2210

Issue #1060

Use 0 instead of 0px, clean-up two line breaks, to fix lint warning;
Three empty CSS blocks could also be removed.

Issue #1739

(Even when the widest-line heuristic goes wrong.)

This prevents it from being repainted whenever the height of the inner
editor briefly changes during a repaint. (At least, it does on Webkit).

Issue #1514

This prevents gutters from suddenly moving below each other as the
editor is scroller horizontally.

Also fixes a problem where individual gutter backgrounds would not
fill the space next to the horiz scrollbar.

Closes #1380