Adding more function to get data as arrays

PingTest
- get_TimesAsArray() uses list comprehension to fit my array
declaration onto one line. This functions returns all of the RTT values
in self.Times as a array of times (all are in milliseconds)

TCP Test
- new function get_Threads_Speed will return a list of lists. This will
return all of the Threads, for the TCP Test object, of a specific data
direction (Upload or Download), as a list of lists of speed
measurements.

Thread
- new function arrayitize_measurements() takes a specific attribute of
the Measurement object (speed or size) and returns a list of the
Thread’s Measurement’s attribute (a way to convert the Thread object
into a list of it’s Measurement’s speeds)

DB API
- recallFile and recallMultipleFiles should now retrieve the specified
files from the database. Both use kwargs, as a few different parameters
need to be specified to retrieve SpeedTestFile’s of specific properties

submain_db
- testing recallMultipleFiles()