Add Arch Dockerfile (#749)

docker/arch/Dockerfile

@@ -0,0 +1,21 @@
+FROM archlinux:base-20210307.0.16708
+
+RUN pacman -Syu --noconfirm && pacman -S wget sudo cmake make git gcc jsoncpp postgresql mariadb-clients --noconfirm
+
+ENV LANG=en_US.UTF-8 \
+    LANGUAGE=en_US:en \
+    LC_ALL=en_US.UTF-8 \
+    CC=gcc \
+    CXX=g++ \
+    AR=gcc-ar \
+    RANLIB=gcc-ranlib \
+    IROOT=/install
+
+ENV DROGON_ROOT="$IROOT/drogon"
+
+ADD https://api.github.com/repos/an-tao/drogon/git/refs/heads/master $IROOT/version.json
+RUN git clone https://github.com/an-tao/drogon $DROGON_ROOT
+
+WORKDIR $DROGON_ROOT
+
+RUN ./build.sh