Convert inline if to block

This was the simplecov coverage is no longer 100%,
because we don't test the railtie (see issue #14).
Move support files to support/dir
Move default settings defs to geo_redirect.rb
Add rake shared example

From http://robots.thoughtbot.com/post/11957424161/test-rake-tasks-like-a-boss
Rename tasks file to .rake
Rename rake task to geo_redirect
Remove Rails dependency from shared rake context
Add example testing rake task
Use load for railtie, not require
Fetch db file to relative path, remove Rails dependency
Rename task to geo_redirect:fetch_db

[ci-skip]