added extra .sh build files

.devcontainer/build_app.sh

@@ -0,0 +1,2 @@
+#!/bin/bash
+cmake --build /workspaces/Pinetime/build --config Release -- -j6 pinetime-app

.devcontainer/make_build_dir.sh

@@ -0,0 +1,2 @@
+#!/bin/bash
+cmake -G 'Unix Makefiles' -DCMAKE_BUILD_TYPE=Release -DUSE_OPENOCD=1 -DARM_NONE_EABI_TOOLCHAIN_PATH=/opt/gcc-arm-none-eabi-9-2020-q2-update -DNRF5_SDK_PATH=/opt/nRF5_SDK_15.3.0_59ac345 /workspaces/Pinetime

.vscode/c_cpp_properties.json

@@ -0,0 +1,17 @@
+{
+    "configurations": [
+        {
+            "name": "Linux",
+            "includePath": [
+                "${workspaceFolder}/**"
+            ],
+            "defines": [],
+            "compilerPath": "/usr/bin/gcc",
+            "cStandard": "gnu11",
+            "cppStandard": "gnu++14",
+            "intelliSenseMode": "linux-gcc-x64",
+            "compileCommands": "${workspaceFolder}/build/compile_commands.json"
+        }
+    ],
+    "version": 4
+}