BUG: Fix dylib versioning flags for old OSX.

  - ld flags -dylib_compatibility_version and -dylib_current_version
    are libtool flags -compatibility_version and -current_version
  - OSX 10.3 does not like the dylib_ prefixes.

Modules/Platform/Darwin.cmake

@@ -27,8 +27,8 @@ SET(CMAKE_SHARED_MODULE_SUFFIX ".so")
 SET(CMAKE_MODULE_EXISTS 1)
 SET(CMAKE_DL_LIBS "")
 
-SET(CMAKE_C_OSX_COMPATIBILITY_VERSION_FLAG -Wl,-dylib_compatibility_version,)
-SET(CMAKE_C_OSX_CURRENT_VERSION_FLAG -Wl,-dylib_current_version,)
+SET(CMAKE_C_OSX_COMPATIBILITY_VERSION_FLAG -Wl,-compatibility_version,)
+SET(CMAKE_C_OSX_CURRENT_VERSION_FLAG -Wl,-current_version,)
 SET(CMAKE_CXX_OSX_COMPATIBILITY_VERSION_FLAG "${CMAKE_C_OSX_COMPATIBILITY_VERSION_FLAG}")
 SET(CMAKE_CXX_OSX_CURRENT_VERSION_FLAG "${CMAKE_C_OSX_CURRENT_VERSION_FLAG}")