refactor(core): rename validation rules changed event
refactor(valdrUtil): rename notNull to notEmpty
chore(docs): add doc for input directive
refactor(core): rename messageKey to message in validation results
refactor(valdrInput): use valdrUtil to check if input has a name attribute
chore(docs): add basic docs to valdrType directive
Merge branch 'master' of https://github.com/netceteragroup/valdr

# By marcelstoer
# Via marcelstoer
* 'master' of https://github.com/netceteragroup/valdr:
  Update README.md