[vim] Fix unescaping of escaped strings for search and replace

Add unit tests.
[css mode] Add simple support for @keyframes

Closes #2161
[less] don't confuse less mode..

..with the newly added simple support for @keyframes
Merge branch 'master' of https://github.com/marijnh/CodeMirror
Expose triggerOnKeyPress and triggerOnKeyUp for testing
[vim] Use key character instead of key identifier to map all character keys without modifiers
Added "historyAdded" doc event.

Added a doc event "historyAdded" which is dispatched when a new entry is added to the document history. It is not dispatched when a history entry is amended. This allows CM's history to be integrated easily into application level undo/redo.

Signed-off-by: Grant Skinner <info@gskinner.com>
Fix trailing whitespace from c7e4ad741dbfc62ab2e4394c1945cd048f99a727
Fix bug in keymap table, properly bind Ctrl-Up
Signal overwriteToggle event

Issue #2180
[foldcode addon] Add an isFolded method
[css mode] Update Grid Layout property names

Some properties were outdated and some other were missing according to last
version of the CSS Grid Layout spec:
http://www.w3.org/TR/css3-grid-layout/#property-index
Remove remaining uses of tabMode and enterMode in demos
[continuecomment addon] Allow continuing block comment from first line.
[merge addon] Add trailing semicolon too diff_match_patch.js

(otherwise there is an error if all is minified in one file)
[clojure mode] Add angle brackets to symbol characters
[sql plsql] add keyword: elseif, returns
[sql plsql] Add builtin: bigserial, serial...

... UNLOGGED, add keyword: cascade
[runmode addon] Fix missing parameter in runmode.node.js

Closes #2188
[docs & project page] Typo fixes.