Adding Playdate compile instructions to the project

playdate/INSTRUCTIONS.md

@@ -0,0 +1,15 @@
+C project
+  To run in the simulator:
+    cd ./build
+    rm -R ../ThePlaytrix.pdx ./*
+    cmake ..
+    make
+
+  To run on the device:
+    cd ./build-device
+    rm -R ../ThePlaytrix.pdx ./*
+    cmake -DCMAKE_TOOLCHAIN_FILE=${PLAYDATE_SDK_PATH}/C_API/buildsupport/arm.cmake -DCMAKE_BUILD_TYPE=Release ..
+    make
+
+Lua project
+  pdc -s Source ThePlaytrixLua.pdx