Initial commit of working buttons (regular size only)

- Boilerplate typography, agora colors
- Mixins for generating all colors for a button based on a base

Change-Id: I3a9bb6a5e7b50ac8388a36173fa07e6ba0198679
Added classes for disabled/hover/active

Change-Id: I4be02fc75d07d71a4070134e5b7b990d36d641fe
Merge "Initial commit of working buttons (regular size only)"
Merge "Added classes for disabled/hover/active"