Added a simple find_package module for TinyXML.cmake;
 * from: https://github.com/ros/cmake_modules/blob/0.3-devel/cmake/Modules/FindTinyXML.cmake
Reworked glxspheres/CMakeLists.txt
  (1) find_package(GLU REQUIRED);
  (2) added the variable glxsphere_SRC (instead of aux_source_directory);
  (3) added appropriate entry to within target_link_libraries (GLU_LIBRARIES).
Updated CMakeLists.txt to fix ValveSoftware/vogl/issues/16;

src/CMakeLists.txt:
 (1) Added cmake variable HAS_UPDATED_LIBUNWIND;
 (2) Added message explaining what HAS_UPDATED_LIBUNWIND does;
 (3) Moved add_subdirectory(libbacktrace), add_subdirectory(libbacktrace_test);
     below other add_subdirectory(...) commands;

src/libbacktrace/CMakeLists.txt:
 (1) add_definitions(-DCMAKE_HAS_UPDATED_LIBUNWIND) if HAS_UPDATED_LIBUNWIND=true

src/libbacktrace/btrace.cpp:
 (1) added ifdef check CMAKE_HAS_UPDATED_LIBUNWIND
Reworked src/vogltrace/CMakeLists.txt to fix issue 16;
 (1) requires a symbolic link between libturbojpeg.so.0 to
     libturbojpeg.so (within the search path)
 (2) Switched ${X11_X11_LIB} to ${X11_LIBRARIES}
 (3) Moved project definition to top of the file;
Updated voglcore/CMakeLists.txt removing lzma_*.cpp;
(1) Replaced compiling of lzma and lzmadec with ${LZMA_LIBRARIES};
(2) Added include for lzma;
Reworked src/voglen/CMakeLists.txt to not compile tinyxml;