Add `initText` option for bootstrapping the input text

Test Plan:
1. python -m SimpleHTTPServer 8000
2. Visit http://localhost:8000 and confirm that "Mountain View, CA"
appears in location dropdown

Reviewers: alpert

Differential Revision: http://phabricator.khanacademy.org/D3599
Add `initText` option for bootstrapping the input text

Test Plan:
1. python -m SimpleHTTPServer 8000
2. Visit http://localhost:8000 and confirm that "Mountain View, CA"
appears in location dropdown

Reviewers: alpert

Differential Revision: http://phabricator.khanacademy.org/D3599