Moved dialogs to the body

When the editor was placed in a bootstrap modal and jquery validate was used, errors were thrown when a modal was displayed, image, video, etc... form the editor.  By moving the dialogs to the body this error was not thrown any longer because there were no longer nested forms within the modal.
Merge branch 'dialogs' of https://github.com/dfisch/summernote into dialogs
Cosmetic spell fix: dettach -> detach
Make sure to clean-up dialogs when destroying summernote
Allow overriding default dialog z index in order to show dialogs on top of editor dialog
Merge branch 'dialogs' into develop

Conflicts:
	dist/summernote.js
	dist/summernote.min.js
	src/js/Renderer.js
Updated dist files