add Eq instance, fix bug on Object(length > 1) parsing.
update export list. add fail function.
add examples.
aeson compatible Either bahavior.
add test, version bump up.
travis
Merge branch 'develop'

new feature:
* add Eq instance to Value.
* add exports: FromJSON(..), fail.

changes:
* Either bahaviour(aeson compatible).

bug fix:
* fail on parsing object which has more then one elements.