add signature_pad dependency to fix #2
added current steps
added missing script tag for the main library
Update README.md
Fixed get(0) -> [0]

I get an exception when I use `canvas.get(0)`. Maybe it's just an angular 1.0.x / 1.2.x thing, but probably better to go with the one that works everywhere, right?
applied same get(0) -> [0] fix to built file
Bugfix: Explicitly typed button as a button

The default type for button is `submit`, which affects all parent forms by calling `submit()` on them.
Bugfix: Expand to fill container, not entire window

If this is to be loaded in a modal or as part of a form it should only take up the whole window if that div takes up the whole window.

For Example:
```html
<div class="modal">
  <div class="mr-signature-pad"></div>
</div>
```
Merge remote-tracking branch 'origin/patch-2'
Merge remote-tracking branch 'origin/patch-3'