CMake improvements

[onurbingol]

• This PR updates CMake configuration files to make it more modular and CMake-native.
• There are some major changes (discussed below) in addition to the minor changes (documented in the code)

Added options

• JU_ENABLE_PYTHON_BINDINGS enables building the python bindings
• JU_PYTHON_BINDING_VERSION allows setting custom python version without editing python/CMakeLists.txt file
• JU_ENABLE_CAMERA_VIEWER enables building the application under camera/camera-viewer
• JU_ENABLE_V4L2_DISPLAY enables building the application under camera/v4l2-display
• JU_ENABLE_V4L2_CONSOLE enables building the application under camera/v4l2-console
• JU_ENABLE_VIDEO_VIEWER enables building the application under video/video-viewer
• JU_ENABLE_GL_DISPLAY_TEST enables building the application under display/gl-display-test
• JU_ENABLE_WEBRTC_SERVER enables building the application under network/webrtc-server
• JU_ENABLE_RTSP_SERVER enables building the application under network/rtsp-server

It is possible to use CMAKE_INSTALL_PREFIX to change the installation directory. This option also works if jetson-utils project is added as a submodule and install prefix is changed from the parent.

By default jetson-utils use C++11, but if it is set to a different standard at the parent level, it will use it.

Usage example

$ mkdir -p build
$ cd build
$ cmake .. -DJU_ENABLE_PYTHON_BINDINGS=ON -DJU_PYTHON_BINDING_VERSION=3.9

Note: You would also be able to see all the options under JU prefix if you use cmake-gui.

Added build targets

If you are building jetson-utils as a standalone project, you should be able to have an option for uninstall, i.e.

$ cd build
$ make uninstall

CMake example on how to use jetson-utils library

cmake_minimum_required(VERSION 3.11)
project(my_project LANGUAGES CXX VERSION 1.0)

include(GNUInstallDirs)
include(FetchContent) 

FetchContent_Declare(
  jetson-utils
  GIT_REPOSITORY https://github.com/onurbingol/jetson-utils.git
  GIT_TAG        onur/cmake-improvements
)
FetchContent_MakeAvailable(jetson-utils)

# the executable name would be "my_project_app"
cuda_add_executable(${PROJECT_NAME}_app
  ${CMAKE_CURRENT_LIST_DIR}/src/main.cpp
)
target_link_libraries(${PROJECT_NAME}_app
  jetson-utils
)

install(
  TARGETS
    ${PROJECT_NAME}_app
  DESTINATION
    ${CMAKE_INSTALL_BINDIR}
)

[onurbingol]

@dusty-nv this is almost done, I need to test a little bit more. I'd be happy if you could also test the final changes.

[onurbingol]

@dusty-nv tested on Jetson Nano and Jetson Orin Nano, it looks good to me. Also added some details on the changes I made. There are no changes in the code, just the CMakeLists.txt files.

You might see that there are no __init__.py files in the repo. Those files can be configured/created automatically by CMake, which seems a more convenient solution to me (git complains about those __init__.py files when the OS is using a case insensitive file system)