Include the OpenAL headers using the "al.h" form, as recommended by its CMake finder script
Fix system_other implementation by adding an Init() and fixing the wrong const
MacOSX: Add initial support in CMake build infra
Rewrite the CBotString::s_keywordString initialization to use a function

That makes this code compatible with older libstdc++ versions such as Mac OSX's 4.2.1
On MacOSX, use std::tr1::array instead of std::array

That makes this code compile with older libstdc++ versions such as Mac OSX's 4.2.1
Drop usage of std::string::append in favour of explicit +=

That makes this code compile with older libstdc++ versions such as Mac OSX's 4.2.1