A first stab at a 64-bit labbrick driver.

--BRJ
Minor sequence updates

--BRJ
Fix syntax errors

Still not functional because I cannot seem to open a handle to a device.

--BRJ
Working version

Caveats: Can only connect to first serial number. Also, only allows
setting frequencies in multiples of 100 kHz.

--BRJ
Merge branch 'feature/labbrick64' into develop