Added auto_prepare feature...

Auto prepare now allows you to execute queries on the database without having to manually go through $wpdb->prepare(). You can now pass all your variables directly to the the get_ method! It also handles detection of the output method, as the first or last argument passed after the query.

For output method detection to work, the values of the OBJECT, OBJECT_K, ARRAY_A and ARRAY_N constants have been changed to include a random string, so as to hopefully eliminate the probability of a collision with a variable intended to be used as a variable in the query.

To prevent conflict with the other methods, get_the_* versions of the var, row and col methods have been created. These however do not allow specifying of the X/Y coordinates, but frankly those are seldom used anyway. There's also one for get_results, just to be on the safe side.

Added the following methods:
- auto_prepare()
- get_the_var()
- get_the_row()
- get_the_col()
- get_the_results()

Updated the following methods:
- query() to use auto_prepare()