[mac] Fixes disallowed size_t vs int* comparison, which used to be specially included for Darwin systems but does not seem relevant anymore.

git-svn-id: https://svn.astron.nl/casarest/trunk/casarest@8755 4215e939-9a1b-0410-8a78-adf775e9a44f
[mac] Add boost_system library to avoid missing symbols.

git-svn-id: https://svn.astron.nl/casarest/trunk/casarest@8756 4215e939-9a1b-0410-8a78-adf775e9a44f