[PATCH] cmd: Added set /a

[Marvin]

Hi,

While running your changed tests on Windows, I think I found new failures.
Being a bot and all I'm not very good at pattern recognition, so I might be
wrong, but could you please double-check?
Full results can be found at
http://testbot.winehq.org/JobDetails.pl?Key=10334

Your paranoid android.


=== WNT4WSSP6 (32 bit) ===
batch.c:223: Test failed: unexpected char 0x34 position 0 in line 118 (got '4', wanted '3')
batch.c:223: Test failed: unexpected char 0x34 position 0 in line 120 (got '4', wanted '11')
batch.c:223: Test failed: unexpected char 0x30 position 0 in line 24 (got '0', wanted '2')
batch.c:223: Test failed: unexpected char 0x31 position 0 in line 30 (got '12', wanted '2')
batch.c:223: Test failed: unexpected char 0x2d position 0 in line 42 (got '-2147483648', wanted '0')
batch.c:223: Test failed: unexpected char 0x33 position 0 in line 46 (got '3', wanted '1')
batch.c:223: Test failed: unexpected char 0x35 position 0 in line 124 (got '5', wanted '6')
batch.c:223: Test failed: unexpected char 0x35 position 0 in line 130 (got '5', wanted '2')
batch.c:223: Test failed: unexpected char 0x35 position 0 in line 140 (got '5', wanted '1')
batch.c:223: Test failed: unexpected char 0x35 position 0 in line 146 (got '5', wanted '10')