Account Profile Display, Edit, Update Functionalities

In this pull request, my branch has updates on Account Profile service, which Donnie has halfway done.

view profile: Logged-in users can check their personal profile from the menu at the right side of the navbar, or clicking on the gear icon on the home page.
edit profile: Users can click on the update button to activate the profile edit mode of their profile. They cannot change email, password and gender.
- Currently, users can edit their found_roommate status into YES to remove their profiles from the Roommates page.
- A hidden checkpoint will compare the session-stored email with the email on the edit template. It kicks the user(hacker) off the website if a difference is detected.
update profile: Once save button is clicked on, data changed by the user will be stored in the database and send the user back to the profile view mode.
- Restriction rules from the registration page works here.
- If nothing is changed, no saving process will be done and a warning message will be sent to the user through flash.

The followings are related with this PR:

TommyCheng023 / RoomieConnect