docs: add cmake example

CMakeLists.txt

@@ -2,31 +2,33 @@ cmake_minimum_required(VERSION 3.12)
 
 project(squirrel)
 
-# Override this in your build of the library! Otherwise, it will default to 1 key.
+# target_compile_definitions(squirrel PUBLIC SQUIRREL_KEYCOUNT=your_keycount)
+# Override this using the above line in your build of the library! Otherwise, it
+# will default to 1 key.
 add_compile_definitions(SQUIRREL_KEYCOUNT=1)
 
-if (CMAKE_BUILD_TYPE STREQUAL "Debug")
-        set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
-        add_compile_options(-Og)
+if(CMAKE_BUILD_TYPE STREQUAL "Debug")
+  set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+  add_compile_options(-Og)
 else()
-       add_compile_options(-Os)
+  add_compile_options(-Os)
 endif()
 
 # Generate a static library archive.
-add_library(squirrel STATIC
-        src/squirrel.c
-        src/squirrel_quantum.c
-        src/squirrel_keyboard.c
-        src/squirrel_key.c
-        src/squirrel_consumer.c
-        src/squirrel_init.c
-        src/squirrel_keymap.c
-        src/squirrel_split.c
-        )
+add_library(
+  squirrel STATIC
+  src/squirrel.c
+  src/squirrel_quantum.c
+  src/squirrel_keyboard.c
+  src/squirrel_key.c
+  src/squirrel_consumer.c
+  src/squirrel_init.c
+  src/squirrel_keymap.c
+  src/squirrel_split.c)
 
 target_include_directories(squirrel PUBLIC include)
 set_target_properties(squirrel PROPERTIES PUBLIC_HEADER include/squirrel.h)
 
-if (BUILD_TESTING)
-        add_subdirectory(tests)
+if(BUILD_TESTING)
+  add_subdirectory(tests)
 endif()