Fixed score counter

Score will only be written when the score is above 0.
Score variable begins at -1 so that the start word doesn't count.
document ready wrap

wrapped it all in a document ready function.
WPM counter written in
More info to the page

About and Instructions add
MaxWPM js

doesn't work right now. Pushing the variable into the array overwrites
the value, not append a new one in.
Marked up maxWPM box
made maxWPM JS work
Merge pull request #19 from yuanphoon/14_WPM_timer_add

14 wpm timer add