It causes side effects on iOS

On old IEs, don't do this check, since it sometimes raises weird
exceptions, and re-focusing is harmless there.

Remove a bunch of regexp kludges that never really worked.

Will need to be tested more rigorously (I only tried the existing demo).

As a die-hard vim addict, long ago, I retrained myself to type Ctrl-[ to
leave insert mode. This sends the same control sequence as escape in
many other places, actually, and this patch brings this functionality to
CodeMirror.

From vim's :help ctrl-[

                                        *i_CTRL-[* *i_<Esc>*
<Esc> or CTRL-[
    End insert or Replace mode, go back to Normal mode.
    Finish abbreviation.
    Note: If your <Esc> key is hard to hit on your keyboard, train
    yourself to use CTRL-[.

Typing CTRL-[ is particularly easy when caps-lock is remapped
to being another CTRL key, since now neither hand needs to move away
form the homerow, and both little fingers just slide a little, the left
little finger slides to the right to where caps lock used to be, and the
right little finger slides a little bit up to the '[' key

This allows the xml mode to return a style with space separated classes
and still work. I didn't use /\btag\b/ since that can match "tag-foo".

This stores the previous value for a mode property if an extension
overwrites it with a new value. The old value is stored in a property
prefixed with an underscore (e.g. "_token"). This allows extensions to
piggyback the old value by still being able to access it.

…de object

…RFC 2616

array initialization (one entry per line) results in extra indentation from second element onwards:
ex:-
const string[] fields = {
  "one",
    "two",
    "three"
};

See discussion in #984

This adds a blankLine method that calls the current mode's blankLine if
it has one. It has allows switching on a blank line if "\n" is specified
for "open" or "close".

moveByLines was changed to better keep track of the previous
action.  For example, if moveToEol was the previous action,
moving up or down should stay at Eol regardless of line length.

    Use newlineAndIndentContinueComment by default, falling back to newlineAndIndent if the former command is not defined.
    Same behavior is made default for Enter key in insert mode.

Closes #1026

…own and mouseup

Various other style fixes. Updates to comments.

…own mode

It may not provide these methods.

Closes #1051

…alues

Issue #1026