install kivyMD from git code example

Example 1: install kivyMD from git

git clone https://github.com/kivymd/KivyMD.git --depth 1
cd KivyMD
pip install .

Example 2: install kivyMD from git

# Master branch:
python3 -m pip install git+https://github.com/HeaTTheatR/KivyMD.git
# Specific branch:
python3 -m pip install git+https://github.com/HeaTTheatR/KivyMD.git@stable
# Specific tag:
python3 -m pip install git+https://github.com/HeaTTheatR/KivyMD.git@0.100.2
# Specific commit:
python3 -m pip install git+https://github.com/HeaTTheatR/KivyMD.git@f80d9c8b812d54a724db7eda30c4211d0ba764c2

# If you already has installed KivyMD
python3 -m pip install --force-reinstall git+https://github.com/HeaTTheatR/KivyMD.git