Closes #1744

Issue #1741

When the cursor blink rate is zero (or negative) the cursor should not
blink.  Previously, it was blinking as fast as possible when the rate
was zero.

Issue #1739

Issue #1739

Issue #1735

Issue #1743

current delay of 100ms between selection of word to highlighting is almost instantaneous.

To prevent a lot of DOM nodes from sticking around after measuring a
long line, easing the pressure on the GC.

Issue #902

It seems recent versions of Chrome/Blink fire the handler first,
and then clear the selection.

Issue #1730

(Works in real browsers.)

Closes #1726

 * Updated for CodeMirror 3 - added comment clock declarations

 * Corrected handling of macro calls with a body

 * Added extra features for detecting variables within strings and
   methods & properties of objects

 * Corrected the detection of methods and properties of Java objects

The were some minor issues w.r.t. where exactly an `stex` or `python`
inner mode starts and where the outer `rst` mode resumes; fixed.

Previously, if you tried to move further down the document than exist
the cursor would not move down.  This sets selectionEnd.line to be
no greater than the total length of the document.