Add private feature for profiles

[JonathanGarro]

Some users don't want their profile information to be available to the public. Need to add a checkbox that marks their profile as private. Some options:

• Add boolean column in user table for "private_profile"
• When viewing profile as non-logged in user, it would show the person's name but redact all other info
• Could also add function to new_user route in Flask that appends their profile URL to the disallow inside the robots.txt file

[JonathanGarro]

Released with 1.5.0