File location updated

Moved OFDMA files to MAC folder and removed extra class file
Added example test to TX side OFDMA
Made TxOFDMA into a class.

RxOFDMA was changed and adapted for testing purposes, so it still need
many changes.
Merge remote-tracking branch 'origin/ofdma' into ofdma

Conflicts:
	sdruTxRx/MAC/TxOFDMA.m
Fixed TxOFDMA that was uploaded

The previous file had some mistakes, caused by committing without
synching.
Future MAC test to complete
Made TxOFDMA and RxOFDMA into classes

Both classes can be called using the step() syntax.
added test with PHY layer
Changed OFDMA script to test folder

Also changed its name from "ZZ_Script_OFDMA" to "testOFDMA"
removed functions to be replaced by classes from ofdma
Merge branch 'ofdma'