enable or disable plugins with build args

Dockerfile

@@ -1,5 +1,15 @@
 FROM alpine:3.10
 
+ARG FACEBOOK=1
+ARG STEAM=1
+ARG SKYPEWEB=1
+ARG TELEGRAM=1
+ARG HANGOUTS=1
+ARG SLACK=1
+ARG SIPE=1
+ARG DISCORD=1
+ARG ROCKETCHAT=1
+
 ENV BITLBEE_VERSION 3.6
 ENV FACEBOOK_VERSION v1.2.0
 ENV STEAM_VERSION a6444d2
@@ -56,51 +66,51 @@ RUN addgroup -g 101 -S bitlbee \
  && make \
  && make install \
  && make install-dev \
- && cd /tmp \
+ && if [ ${FACEBOOK} -eq 1 ]; then cd /tmp \
  && git clone https://github.com/bitlbee/bitlbee-facebook.git \
  && cd bitlbee-facebook \
  && git checkout ${FACEBOOK_VERSION} \
  && ./autogen.sh \
  && make \
  && make install \
- && strip /usr/lib/bitlbee/facebook.so \
+ && strip /usr/lib/bitlbee/facebook.so; fi \
- && cd /tmp \
+ && if [ ${STEAM} -eq 1 ]; then cd /tmp \
  && git clone https://github.com/bitlbee/bitlbee-steam.git \
  && cd bitlbee-steam \
  && git checkout ${STEAM_VERSION} \
  && ./autogen.sh --build=x86_64-alpine-linux-musl --host=x86_64-alpine-linux-musl \
  && make \
  && make install \
- && strip /usr/lib/bitlbee/steam.so \
+ && strip /usr/lib/bitlbee/steam.so; fi \
- && cd /tmp \
+ && if [ ${SKYPEWEB} -eq 1 ]; then cd /tmp \
  && git clone git://github.com/EionRobb/skype4pidgin.git \
  && cd skype4pidgin/skypeweb \
  && git checkout ${SKYPEWEB_VERSION} \
  && make \
  && make install \
- && strip /usr/lib/purple-2/libskypeweb.so \
+ && strip /usr/lib/purple-2/libskypeweb.so; fi \
- && cd /tmp \
+ && if [ ${TELEGRAM} -eq 1 ]; then cd /tmp \
  && git clone --recursive https://github.com/majn/telegram-purple \
  && cd telegram-purple \
  && git checkout ${TELEGRAM_VERSION} \
  && ./configure --build=x86_64-alpine-linux-musl --host=x86_64-alpine-linux-musl \
  && make \
  && make install \
- && strip /usr/lib/purple-2/telegram-purple.so \
+ && strip /usr/lib/purple-2/telegram-purple.so; fi \
- && cd /tmp \
+ && if [ ${HANGOUTS} -eq 1 ]; then cd /tmp \
  && hg clone https://bitbucket.org/EionRobb/purple-hangouts -r ${HANGOUTS_VERSION} \
  && cd purple-hangouts \
  && make \
  && make install \
- && strip /usr/lib/purple-2/libhangouts.so \
+ && strip /usr/lib/purple-2/libhangouts.so; fi \
- && cd /tmp \
+ && if [ ${SLACK} -eq 1 ]; then cd /tmp \
  && git clone https://github.com/dylex/slack-libpurple.git \
  && cd slack-libpurple \
  && git checkout ${SLACK_VERSION} \
  && make \
  && make install \
- && strip /usr/lib/purple-2/libslack.so \
+ && strip /usr/lib/purple-2/libslack.so; fi \
- && cd /tmp \
+ && if [ ${SIPE} -eq 1 ]; then cd /tmp \
  && git clone https://github.com/tieto/sipe.git \
  && cd sipe \
  && git checkout ${SIPE_VERSION} \
@@ -108,8 +118,8 @@ RUN addgroup -g 101 -S bitlbee \
  && ./configure --build=x86_64-alpine-linux-musl --host=x86_64-alpine-linux-musl --prefix=/usr \
  && make \
  && make install \
- && strip /usr/lib/purple-2/libsipe.so \
+ && strip /usr/lib/purple-2/libsipe.so; fi \
- && cd /tmp \
+ && if [ ${DISCORD} -eq 1 ]; then cd /tmp \
  && git clone https://github.com/sm00th/bitlbee-discord.git \
  && cd bitlbee-discord \
  && git checkout ${DISCORD_VERSION} \
@@ -117,13 +127,13 @@ RUN addgroup -g 101 -S bitlbee \
  && ./configure --build=x86_64-alpine-linux-musl --host=x86_64-alpine-linux-musl --prefix=/usr \
  && make \
  && make install \
- && strip /usr/lib/bitlbee/discord.so \
+ && strip /usr/lib/bitlbee/discord.so; fi \
- && cd /tmp \
+ && if [ ${ROCKETCHAT} -eq 1 ]; then cd /tmp \
  && hg clone https://bitbucket.org/EionRobb/purple-rocketchat -r ${ROCKETCHAT_VERSION} \
  && cd purple-rocketchat \
  && make \
  && make install \
- && strip /usr/lib/purple-2/librocketchat.so \
+ && strip /usr/lib/purple-2/librocketchat.so; fi \
  && rm -rf /tmp/* \
  && rm -rf /usr/include/bitlbee \
  && rm -f /usr/lib/pkgconfig/bitlbee.pc \