udacity_project_4 | Udacity project 4 for Full stack nanodegree program

##Session design choices Session object has all the attributes required by instructions.
To use the provided API, please go to https://udacity-kkproject4.appspot.com/_ah/api/explorer
Update the value of application in app.yaml to the app ID you have registered in the App Engine admin console and would like to use to host your instance of this sample.
Update the values at the top of settings.py to reflect the respective client IDs you have registered in the Developer Console.
Update the value of CLIENT_ID in static/js/app.js to the Web client ID
Run the app with the devserver using dev_appserver.py DIR, and ensure it's running by visiting your local server's address (by default localhost:8080.)
sessionType is a repeated field since a session could be of several types
highlights is a repeated field
duration is a field where input is meant to be in full hours and then it is internally changed to seconds
Speaker is a separate entity which has to be added when creating a Session entity. Separating speakers from sessions allows easier querying for speaker sessions and makes caching more efficient
Session is a child of Conference, which seems logical given that all Sessions must be related to a Conference
date, startTime and duration properties are Date, Time, and Integer(seconds) properties so they can be used in filtering
conferenceSessionByTime() - A user can find sessions for a particular conference that start before/after a specified time
sessionsInTimeLimitLessThanDuration() - A user can select earliest and latest starting time for a session and a maximum duration in hours.
First query for all Session keys that are before 7pm.
After we have all the keys for those sessions we can make another query to get all the Sessions that are not "workshop" and whose keys are included in the array that we got from the first query
Query for all Sessions that are before 7pm.
make another variable that holds the array of sessions that we want to return
Iterate through each Session that we got from the first query and check if it is a "workshop".
Append it to the newly created array if it is not