Session Handling

LL-3:  Updated login service to return plain_text/string of the session
identifier which client will use to identify itself on future requests.
MySQL object (contains active session connection) update to perform
simple insert/update queries (params need altering).  Created (simple)
custom SessionTracking hashmap-based structure to store sessionid/MySQL
key/value pairs.  Created test REST component to perform database
inserts with the body being a simple string to be insterted into a
test_table in the database.

InsertTest class currently accepts the sessionid as a Header, will be
changed.

MySQL object currently only connects to default test schema/database
when forming connection.