[perl mode] Include $ in wordChars

Issue #2426
Remove diff_match_patch file from distribution, link cdnjs instead

Issue #2529
[rulers addon] Support color, width, and lineStyle options
[foldcode addon] Support foldOptions option for per-editor defaults
[show-hint addon] Add hintOptions option, sanitize interface
Prevent error when trying to find a view cutting point at end of document

Issue #2528
mode_test.js: refactor to use array of objects.
mode tests: optionally show mode state after every token.

Doesn't show states (but shouldn't crash) on old browsers.
[test runner] Top-align mode test states
Revert intentionally broken but unintentionally committed test
[cypher mode] Add UNWIND keyword
[match-highlighter addon] Use primary selection, not first one

Closes #2539
[markdown mode] Fix code block styling after indented line
[markdown mode] Fix XML styling in Markdown mode

Fix the condition when XML styling should be invoked.
Also add test cases.
[dylan mode] Add module loading shim

Closes #2533
fix crash when showing context menu
fix problems reporting correct character bounds for space at end of wrapped line
Merge branch 'master' of https://github.com/marijnh/CodeMirror