tests: Adding 'tests' directory to ibssa tree

Tests directory will contain testing utilities used
for testing and verification of ibssa.

'loadsave' utility was added. It is used for loading
or saving SSA DB to or from disk.

Signed-off-by: Ilya Nelkenbaum <ilyan@mellanox.com>
Signed-off-by: Hal Rosenstock <hal@mellanox.com>