Don't bind to specific json-editor version

This patch allows patch and minor version updates but disallows major (1.0.0) json-editor updates.
on-change event callback receives new editor value
Merge pull request #5 from sochka/patch-1

Don't bind to specific json-editor version
Merge pull request #6 from sochka/patch-2

on-change event callback receives new editor value
bumped version to 0.1.2