Add stuff for cmake find_package

- Add build* to gitignore
- Fix year in license file
- other changes are result of clang-format

backends/desktop/glad/CMakeLists.txt

@@ -1,4 +1,8 @@
 cmake_minimum_required(VERSION 3.22)
 
 add_library(glad source/glad.c)
-target_include_directories(glad PUBLIC include)
+target_include_directories(glad
+    PUBLIC
+    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
+    $<INSTALL_INTERFACE:include>
+)