Update development environment docs

[Michael Porras]

A few steps in setting up a development environment have deviated from the code. The API service is now set to 7780. A cloud entity needs to be created before A region. Pymysql is now included in the database connection specifier.

[Michael Porras (mporras6856)]

Document port change was completed in https://review.openstack.org/#/c/439909/

Document region create fix was completed in https://review.openstack.org/#/c/440790/

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/448248

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/448248
Committed: https://git.openstack.org/cgit/openstack/craton/commit/?id=b571719f67c4842a29db5cfe812a3b4d0bfda4e4
Submitter: Jenkins
Branch: master

commit b571719f67c4842a29db5cfe812a3b4d0bfda4e4
Author: Michael Porras <email address hidden>
Date: Tue Mar 21 14:21:15 2017 -0500

    Docker and dev Documentation update

    Updating dev install documentation to include pymysql database connection.
    Updating docker documentation to gather bootstrap auth credentials and
    change api port.

    Change-Id: I5df061749f7c4143c7d2b3f7f6fecddd5be0223b
    Closes-Bug: #1674731