Add SQLite3 adapter for Rails 4 support.
Move license into a separate file.
Update deprecated Rails 4 methods.
Remove sqlite adapter from Rails 3.x.
Add support for force-creation of views

Create table has a `:force` option that will drop tables if they exist
when passed. This adds support for the same option when creating views.
Specify dev deps in the Gemfile to utilize platforms.
Revert "Remove sqlite adapter from Rails 3.x."

This reverts commit 852b73f015379f5f456282e96bef71045fe9ca47.