have to set IFRAME manually

ichord/At.js/issues/160
fix #178 hide view while clicking somewhere else
change space_after to suffix

Add an `hide_without_suffix` option which will force it not to hide view without
suffix
And apply to contenteditable mode

relate to #162 #164
refactor inserting of contenteditable

close #109
fix caret position error after inserting
update version to v0.5.0
Merge `v0.5.0`