Fully implement and test the `templates/user/organization.html` page

[chriscarrollsmith]

• Needs functionality to interact with the various routes in organization.py and role.py
• Needs to be able to handle zero, one, and many users/roles
• Should only render if the user is an organization member; should only enable functionality the user has access to
• Also need to test profile.html with a user belonging to more than one organization

[chriscarrollsmith]

Currently the page correctly renders, at least for an organization with one member, showing two panels: a summary of all the organization roles, and a summary of all the organization members. The next task is to add functionality for inviting new members to the organization.

[chriscarrollsmith]

Also need forms for creating, updating, deleting roles using the routes defined in role.py