Add pico tf lib

.gitmodules

src/PC/sign_language_detector.ipynb

src/hardware/CMakeLists.txt

src/hardware/lib/pico-tflmicro

src/hardware/main.c

src/pc/dataset/amer_sign2.png

src/pc/dataset/amer_sign3.png

src/pc/dataset/american_sign_language.PNG

src/pc/dataset/sign_mnist_test.csv

src/pc/dataset/sign_mnist_test/sign_mnist_test.csv

src/pc/dataset/sign_mnist_train.csv

src/pc/dataset/sign_mnist_train/sign_mnist_train.csv

src/pc/sign_language_detector.ipynb

src/pc/sign_model.keras