Add regression test on deterministic encryption

Signed-off-by: Daniel Thomas <drt24@cam.ac.uk>
State what R is for

Signed-off-by: Daniel Thomas <drt24@cam.ac.uk>
G is produced by xoring the two halves of the hmac together as the hmac itself is too big

Signed-off-by: Daniel Thomas <drt24@cam.ac.uk>
Bkdsa is 384 bytes => 3072 bits => 128 bits of security. Not 16 bytes that would be silly.

Signed-off-by: Daniel Thomas <drt24@cam.ac.uk>
Remove timezone hack from GaeThread as appengine is fixed now

Signed-off-by: Daniel Thomas <drt24@cam.ac.uk>
Fix MConcurrencyTest to use correct value for total which varies with REPEATS rather than hard coded

Signed-off-by: Daniel Thomas <drt24@cam.ac.uk>