Added error messages for additionalProperties and additionalItems.
Minor code documentation fixes.
(fix) minItems and maxItems error messages, current length was undefined.
(fix) Dead links in validate.md
(fix) Object.keys called on non object error in additionalProperties.
Updated compiled.
Updated comment.
Merge remote-tracking branch 'upstream/master'
Merge pull request #73 from topaz1008/master

Several bug fixes, documentation fixes, and additions.