Removes gisicle.

Dockerfile

@@ -8,7 +8,6 @@ ENV RAILS_ENV=production \
     DISCOURSE_REDIS_HOST=redis \
     DISCOURSE_SERVE_STATIC_ASSETS=true \
     DISCOURSE_VERSION=${DISCOURSE_VERSION} \
-    GIFSICLE_VERSION=1.92 \
     PNGQUANT_VERSION=2.12.5 \
     PNGCRUSH_VERSION=1.8.13 \
     JEMALLOC_NEW=3.6.0 \
@@ -68,7 +67,6 @@ RUN curl http://apt.postgresql.org/pub/repos/apt/ACCC4CF8.asc | apt-key add - \
  # Validate install
  && ruby -Eutf-8 -e "v = \`convert -version\`; %w{png tiff jpeg freetype}.each { |f| unless v.include?(f); STDERR.puts('no ' + f +  ' support in imagemagick'); exit(-1); end }" \
  && /tmp/install/pngcrush \
- && /tmp/install/gifsicle \
  && /tmp/install/pngquant \
  && addgroup --gid 1000 discourse \
  && adduser --system --uid 1000 --ingroup discourse --shell /bin/bash discourse \

install/gifsicle

-#!/bin/bash -e
-cd /tmp
-curl -O http://www.lcdf.org/gifsicle/gifsicle-$GIFSICLE_VERSION.tar.gz
-tar zxf gifsicle-$GIFSICLE_VERSION.tar.gz
-cd gifsicle-$GIFSICLE_VERSION
-./configure
-make install
-cd /
-rm -fr /tmp/gifsicle*