Forgive typos basing on Damerau-Levenshtein algo.

At this moment we consider a typo a word with more than two characters that has an edit distance of one.
Move construction of nodes outside of addQuestion.
Clean up unused variables.
Calm down JSHint complaining about commented chars
No longer defer "offscreen" class removal.
Clicking on a kanji question leads to jisho.org
Hopefully less confusing grammar: force vs make.
Directory restructuring by file type.
Remove unused file.
Hopefully less confusing grammar: force vs make.
More user-friendly answers containing articles.

Answering "government" instead of "the government" is now permitted.
However, "take a seat" must be answered as is.
A more flexible typo check mechanism.

Introduce a notion of edit (levenshtein) distance tolerance basing on
the length of the correct answer.
Set edit distance substitution cost to 2.

Distance from "stronk" to "strong" is now 2.
Base tolerance on word instead of a word's length.
Rename and properly init weighted edit distance.
Complete weighted distance matrix init comment.
Somewhat better jslint/hint compliance.
Externalize levenshtein and event handling helper.
Bump version to 0.6.5
Merge 0.6.5 branch 'develop'