Async suggest

[kofifus]

This PR adds the option of running suggest asynchronously allowing updating the display with results as they come, and stopping a suggestion search midway. Also provides much faster performance and smaller memory use on both synchronous and asynchronous suggests.

The suggest function can now be called in one of three ways:

suggest(word, limit [=5])

• runs suggest synchronously, same signature as before

suggest(word, limit [=5], doneFunc, progressFunc) where either doneFunc or progressFunc are defined

• runs suggest asynchronously
• returns undefined
• doneFunc (if given) will be called (with the sorted results array) once the search is done
• progressFunc (if given) will be called (with the new match) whenever a new match is found in the search
• if progressFunc returns===false the current search will be aborted
• will do the equivalent of sleep(0) every 200ms

suggest()

• abort a current search if running

Other changes:

• improve the ordering of permutations returned from the edits1 function
• closes problematic replacementTable suggest behaviour #46
• closes suggest not suggestion capitalized words #48
• closes all-upper-case words should always be considered correct #49

See a working sample in plunkr

[cfinke]

To be honest, at this point, there are so many commits and no clear documentation of each commit that I would feel very uneasy merging in these changes.

[kofifus]

yeah complicated but work very well ... (and documented)

I wrote this for CodeMirror, without async there is an unacceptable wait between pressing the right click and getting the results.

see the gist here: https://gist.github.com/kofifus/4b2f79cadc871a29439d919692099406
see demo https://plnkr.co/edit/0y1wCHXx3k3mZaHFOpHT?p=info

anyways ..

[MikhailTymchukDX]

Personally, I don't inspect every commit when review a PR. I check "Files changed" tab only.
This is very useful improvement, because on long words typo hangs entire page.