docker: Support timezones (#3262)

Dockerfile

@@ -4,7 +4,7 @@ MAINTAINER jp@roemer.im
 # Install system utils & Gogs runtime dependencies
 ADD https://github.com/tianon/gosu/releases/download/1.9/gosu-amd64 /usr/sbin/gosu
 RUN chmod +x /usr/sbin/gosu \
- && apk --no-cache --no-progress add ca-certificates bash git linux-pam s6 curl openssh socat
+ && apk --no-cache --no-progress add ca-certificates bash git linux-pam s6 curl openssh socat tzdata
 
 ENV GOGS_CUSTOM /data/gogs
 

Dockerfile.rpi

@@ -7,7 +7,7 @@ RUN chmod +x /usr/sbin/gosu \
  && echo "http://dl-4.alpinelinux.org/alpine/v3.3/main/"      | tee /etc/apk/repositories    \
  && echo "http://dl-4.alpinelinux.org/alpine/v3.3/community/" | tee -a /etc/apk/repositories \
  && apk -U --no-progress upgrade && rm -f /var/cache/apk/APKINDEX.* \
- && apk --no-cache --no-progress add ca-certificates bash git linux-pam s6 curl openssh socat
+ && apk --no-cache --no-progress add ca-certificates bash git linux-pam s6 curl openssh socat tzdata
 
 ENV GOGS_CUSTOM /data/gogs