Turn on/off sharing in AUTHOR mode

The checkbox is not reflecting the database value, but the change is
sending to database. Will fix this problem later.
css changes missed
Get share bit value from database

For checkbox in author mode.
php script to fetch share bit added
Turn on/off sharing in AUTHOR mode done

Everything should work now.
Merge branch 'master' into jingxian2
Code review for share bit.
  Format Bug for checkbox should be noted in Bugzilla
  and in css/dragoon.css
  Need to re-vamp problem saving and fetching as
   described in the changes to the documentation and in
   new Trello card.
Updating YouTube link for new video.
Query Changed, to get the right problems in "solve a custom problem"
Bug Fix 2403
Handling return value of getInitial using typeof returnvalue==="number"
in case of any checks using getInitial Function
Changes in documentation associated with changing
format of sessions table.
Code review for zero initial value fix:  use test
that initial value is a number.
Also, query in available_problems.php doesn't make sense:  reverted to
original.
Merge branch 'ritesh'
Send the model task to the solutions table.
Update the solutions table using the SQL query:
  UPDATE solutions SET solution_graph = SUBSTRING(solution_graph, 9, LENGTH(solution_graph)-9)
     WHERE solution_graph REGEXP '^{"task":';
Merge branch 'master' into jingxian2
Also, fixed bug with existence test for shareBit in
saveProblem().
Fixed the time interval and time steps check in description editor
Turn on/off sharing after modified solutions table

The checkbox of share bit works for new solutions table.
Add comment about code duplication, referring to Trello card.
Merge branch 'master' into ritesh