Restructuring validate_cookie()

Changing Access-Control-Allow-Origin host
Enabling OPTIONS method for /logout

enabling it to support CORS
Fixing bug while creating group

moved form handling inside try block
Modifying join group URL. Enabling redirections

* Changing join group url
* Adding status 302 for all user not found errors
* Changing cookie value to "None" after logout. Changing a bit of cookie
* Handling for /user/info
Redesigining schema for group for join group

* Now group contains users using the group
* User contains groups he has registered / joined
Adding remove group functionality

* Adding method to remove group from user
* Adding method to remove user from group
* Adding DELETE call for group
Adding CORS decorator
Using CORS decorator for delete group
Modifying request & response headers for CORS

adding response header Access-Control-Allow-Methods get post delete
options

this was the root cause for DELETE & PUT methods to work earlier
Restructuring project-Merging html content with py

Merging repo content of anglur-bootstrap-learning to folder "web"
Now all the project files are in one repo :thumbsup:
Merge branch 'dir-restructure' into dev

Merging the web content repository with the python repository
All project files are in one repo, finally!
Adding EoL marker for html files

Adding the missing EoL marker for all modal dialog template html files
Changing Add-URL API to PUT method

* Modifying app.py with PUT method for /post
* Modifying controller.js to fire PUT method to add new post
* Adding config "apiEndpoint" to controller with the api endpoint
* ^ Used by all the http reuqests
Adding remove Post functionality

* Adding a method to remove post from DB
* Adding a method to handle DELETE request to delete post
* Removing unwanted commented code
Modifying Web UI & controller

* Modifyng remove-group-modal template
* Renamed remove-group-modal to remove-modal
* Now remove-modal is used to handle removal of both group & posts
* Handling events & models to signify what kind of object is being
    removed - Group or Post?
Web UI - generalizing the handling of remove item

* Adding onRemoveItem in controller to handle genric removal of item
* onRemoveItem will intern call respective removal methods
* Handling generic removeal function as click handler for remove
Maintianing uniform handling of cookies

Using the validate_cookie method in every call to check the user info
Merge branch 'user-cookie-detection-uniformity' into dev
Merge branch 'dev'