tor: webtunnel support

- Add webtunnel bridge
- Build from https://code.gri.mw/ardocrat/webtunnel to include binary into the build
- Build and run webtunnel for Android

Reviewed-on: https://code.gri.mw/GUI/grim/pulls/44

scripts/webtunnel.sh

@@ -0,0 +1,51 @@
+#!/bin/bash
+
+cd "$(dirname "$0")"
+
+# Skip if Go not found.
+if ! command -v go >/dev/null 2>&1
+then
+    echo "Go could not be found"
+    exit 0
+fi
+
+go_os=$1
+go_arch=$2
+
+echo "Go build for os: $go_os, arch: $go_arch"
+
+# Setup vars for Android.
+if [[ "$go_os" == "android" ]]; then
+  # Setup NDK root path env.
+  if [[ -z "$ANDROID_NDK_HOME" ]]; then
+    NDK_VERSION=$(cat ../android/app/build.gradle | grep 'ndkVersion' | cut -d \' -f 2)
+    ANDROID_NDK_HOME=$ANDROID_HOME/ndk/$NDK_VERSION
+  fi
+  # Setup NDK host path.
+  if [[ "$(uname)" == "Darwin" ]]; then
+    arch_host=darwin-x86_64
+  else
+    if [[ "$(uname -m)" == "aarch64" ]]; then
+      arch_host=linux-arm64
+    else
+      arch_host=linux-x86_64
+    fi
+  fi
+  # Setup NDK target arch.
+  if [[ "$go_arch" == "arm64" ]]; then
+    arch_bin_prefix=aarch64-linux-android
+  elif [[ "$go_arch" == "arm" ]]; then
+    arch_bin_prefix=armv7a-linux-androideabi
+  else
+    arch_bin_prefix=x86_64-linux-android
+  fi
+
+  # Build for current target.
+  CGO_ENABLED=1 GOOS=$1 GOARCH=$2 CC="${ANDROID_NDK_HOME}/toolchains/llvm/prebuilt/${arch_host}/bin/${arch_bin_prefix}35-clang" CXX="${ANDROID_NDK_HOME}/toolchains/llvm/prebuilt/${arch_path}/bin/${arch_bin_prefix}35-clang++" go build -C "../tor/webtunnel" -ldflags="-s -w" -o "$3" code.gri.mw/WEB/webtunnel/main/client
+else
+  if [[ "$go_os" == "windows" ]]; then
+    extra_flag="-H=windowsgui"
+  fi
+  GOOS=$1 GOARCH=$2 go build -C "../tor/webtunnel" -ldflags="-s -w ${extra_flag}" -o "$3" code.gri.mw/WEB/webtunnel/main/client
+fi
+