Converted Insert to use the new Database Insert method

Sessions' 'Insert' method now uses the Database insert method.
Changed the Insert method to use the Database 'insert' method

Instead of using the Database 'query' method, now uses the Database 'insert'
method as that function now builds the SQL string
Changed the user array passed to the user 'Insert' method

The user array being passed contained array keys that are not
valid columns in the user table. This caused the insert query
to fail.
Converted all INSERT INTO functions to the new 'insert' method

Changed all functions that were building their own INSERT SQL statement.
Those functions now use the Database 'insert' method which builds the
statement instead