Apply my patch from:
http://sourceforge.net/tracker/index.php?func=detail&aid=3269273&group_id=29880&atid=397597
Merge pull request #34 from dveeden/master

MySQL Requirements and Comments fix
check_snmp: Dynamically grow all data structures

Before this patch, there was a constant, MAX_OIDS, that determined the
amount of slots most (but not all - see labels) array data structures
would have. It was set to 8.

Some users would like to use more than that, but rather than bumping the
constant, let's use the same type of logic we already use for labels -
grow the space 8 slots at a time. This will allow us to potentially
support an infinite amount of oids - or at least as many as the
packetsize on the SNMP server allows, which is usually significantly
smaller than infinity, yet often larger than 8.

Signed-off-by: Robin Sonefors <robin.sonefors@op5.com>
check_snmp: Close potential for using uninitialized memory

This was reported by clang, and in order for it to understand attributes
properly, I had to modify the macro that checks for non-gcc compilers.

Signed-off-by: Robin Sonefors <robin.sonefors@op5.com>