Don't only check parent if isValid, also bindable

The problem was parent always returned true because it was a grid,
but bindable (a form) should also have been validated.
BindableController ask related controller for isValid()

BindableController do not know anything about their content so
they should ask related controller if isValid
Merge pull request #203 from Ben-Ho/3.7-ext4-isValid-bugfix

ext4 is valid bugfix
User trlKwf in kwf instead of trl
set server.baseUrl for travis tests
Use better text for message-box
Refine dependencies
Save onContentReady and onElementReady in one array

So all handlers get orderer by priority correctly