Modification to proposal and sample notebook flow

After the proposal is rejected, user will again submit the proposal.
So the proposal form is filled with the initial values of the rejected
proposal.

Sample notebook can be submitted only if the proposal is approved else
will display a message saying 'not permitted'

User after sample notebook submission can anytime edit it.

Modified the template for the reviewer to see the new and old proposal.
Since the ids where same for the collapse element in the loop so there
was problem in javascript.

Profile view modified.
First checks for the user profile. If exists then updates or else
creates a new profile for the user. This will prevent multiple profile
for a single user.[Alternatively, we can give one-to-one relation between
user and profile in models]
Tracking all the activities of the user.

LogEntryManager of django admin is used here.
log_action method takes time, user, objects, action type and message as
its arguments.
For every action, the log_action is called. So that each user activity
is logged.
The logging can be further modified as per our requirement
Model added for activity log. Model is inheriting admins log model

All the activities for a given proposal is available for the reviewer.