Git: set git attributes to automatically manage line endings. (#771)

* Git: set git attributes to automatically manage line endings.

* Git: cleanup gitignore file

.gitignore

@@ -9,22 +9,18 @@ compile_commands.json
 # JetBrains IDEs
 .idea/
 
-
 # Python VirtEnvironments
 .env
 .venv
 env/
 venv/
 
-
 # Python Byte-compiled / optimized files
 __pycache__/
 *.py[cod]
 *$py.class
 
 .obj/
-target_lo/build/
-target_*/build/
 bindings/
 .DS_Store
 .mxproject
@@ -35,4 +31,3 @@ bindings/
 # legendary cmake's
 build
 CMakeLists.txt
-firmware/targets/f2/CMakeLists.txt