removed dependency on Bootswatch flatly theme and repalced it wtih custom code, added a vendor directory so third party plugins are now separate from theme files

When ‘.page-scroll a’ is clicked, the user cannot stop the document
from scrolling until the document has reached the selected section.
This commit allows the user to stop a scroll anytime they want.

Previously the "scroll to Top"-button was always shown.
In my opinion this makes little sense when you are already at the top
and may even lead to confusion (nothing happens when you press the button,
when at top).
So this change will fade the button in and out depending on where you are.
It is leveraging the already implemented scrollPage function.

Signed-off-by: Simon Egli <deadolus@gmail.com>

If we're not disabling the submit button, we can spam click the button and end up with as much mail as we clicked the button.
Keep only id in css selector is speed up the DOM search, and there is less code : )

Currently in the application I'm working on with this theme I use GitHub OAuth2 which redirects after a successful authorization. When GitHub (or any OAuth protocol) redirects this function executes before .page-scroll a is visible in the DOM regardless of document.ready. The click handler should be bound to the listen on the body for clicks to .page-scroll a instead. While this might be a little more expensive than binding to the actual element it fixes a pretty large problem IMO. It's a double edged sword because either you sacrifice a little bit of optimization or easing breaks when a server redirects the app. Even though I realize this is supposed to be a single page template I think login/OAuth is the one exception.