Add new packages and build scripts for various libraries

- Added Nuklear GUI library with build script and configuration.
- Introduced OpenH264 encoder/decoder with build configuration.
- Added PortAudio library for audio I/O with custom build script.
- Included Python Execnet for multi-Python deployment.
- Added Pytest Xdist plugin for distributed testing.
- Introduced Shaderc for shader compilation tools.
- Added Snappy compression library with necessary patches and configuration.
- Included SoundTouch audio processing library with build configuration.
- Added SRT library for secure reliable transport.
- Introduced VapourSynth video processing framework with configuration.
- Added Vid.stab for video stabilization.
- Included WebRTC Audio Processing library with build configuration.
- Added X264 video encoding library with patches for POSIX compliance.
- Introduced X265 video encoder with build configuration.
- Added XKeyboard Config for X keyboard configuration files.
- Included Xorg XKBComp for keyboard description compilation.
- Added Xvidcore MPEG-4 video codec library with configuration.
- Introduced ZeroMQ messaging system with patches and build configuration.
- Added Zimg library for scaling and colorspace conversion.

extra/devil/soversion.patch

@@ -0,0 +1,30 @@
+--- a/DevIL/src-IL/CMakeLists.txt
++++ b/DevIL/src-IL/CMakeLists.txt
+@@ -58,6 +58,7 @@ source_group("Text Files" FILES ${DevIL_TXT} )
+ 
+ if(BUILD_SHARED_LIBS)
+     add_library(IL SHARED ${DevIL_SRCS} ${DevIL_INC} ${DevIL_RSRC} ${DevIL_TXT})
++    set_target_properties(IL PROPERTIES SOVERSION 1)
+ else(BUILD_SHARED_LIBS)
+     add_library(IL ${DevIL_SRCS} ${DevIL_INC} ${DevIL_RSRC} ${DevIL_TXT})
+ endif(BUILD_SHARED_LIBS)
+--- a/DevIL/src-ILU/CMakeLists.txt
++++ b/DevIL/src-ILU/CMakeLists.txt
+@@ -44,6 +44,7 @@ source_group("Resource Files" FILES ${ILU_RSRC} )
+ 
+ # Remove SHARED to create a static library
+ add_library(ILU SHARED ${ILU_SRCS} ${ILU_INC} ${ILU_RSRC})
++set_target_properties(ILU PROPERTIES SOVERSION 1)
+ 
+ 
+ ## ILU requires IL
+--- a/DevIL/src-ILUT/CMakeLists.txt
++++ b/DevIL/src-ILUT/CMakeLists.txt
+@@ -44,6 +44,7 @@ source_group("Resource Files" FILES ${ILUT_RSRC} )
+ 
+ # Remove SHARED to create a static library
+ add_library(ILUT SHARED ${ILUT_SRCS} ${ILUT_INC} ${ILUT_RSRC})
++set_target_properties(ILUT PROPERTIES SOVERSION 1)
+ 
+ ## add link sub library info
+ target_link_libraries(ILUT