Implement SoundEmit modifier

This sound emitter modifier is almost as fully functional as PlasmaMAX's various sound emitter components. Additional functionality was added to C korlib so that artists can specify OGG Vorbis sound files. If korlib is not compiled, only WAVE sounds can be utilized in Korman. This fixes some of the more fiddly bugs related to exporting to CWE that were seen in PyPRP.

Sound nodes to be implemented...

korlib/cmake/FindOgg.cmake

@@ -0,0 +1,30 @@
+if(Ogg_INCLUDE_DIR AND Ogg_LIBRARY)
+    set(Ogg_FIND_QUIETLY TRUE)
+endif()
+
+
+find_path(Ogg_INCLUDE_DIR ogg/ogg.h
+          /usr/local/include
+          /usr/include
+)
+
+find_library(Ogg_LIBRARY NAMES ogg
+             PATHS /usr/local/lib /usr/lib
+)
+
+set(Ogg_LIBRARIES ${Ogg_LIBRARY})
+
+
+if(Ogg_INCLUDE_DIR AND Ogg_LIBRARY)
+    set(Ogg_FOUND TRUE)
+endif()
+
+if (Ogg_FOUND)
+    if(NOT Ogg_FIND_QUIETLY)
+        message(STATUS "Found libogg: ${Ogg_INCLUDE_DIR}")
+    endif()
+else()
+    if(Ogg_FIND_REQUIRED)
+        message(FATAL_ERROR "Could not find libogg")
+    endif()
+endif()