Install gerbil packages globally not locally in the project directory

Former-commit-id: 5928e40721

app/data/container-build/cerc-builder-gerbil/Dockerfile

@@ -16,6 +16,12 @@ RUN apt-get update && export DEBIAN_FRONTEND=noninteractive && export DEBCONF_NO
 RUN mkdir /scripts
 COPY install-dependencies.sh /scripts
 
+# Override the definition of GERBIL_PATH in the base image, but
+# is safe because (at present) no gerbil packages are installed in the base image
+# We do this in order to allow a set of pre-installed packages from the container
+# to be used with an arbitrary, potentially different set of projects bind mounted
+# at /src
+ENV GERBIL_PATH=/.gerbil
 RUN bash /scripts/install-dependencies.sh
 
 # Needed to prevent git from raging about /src

app/data/container-build/cerc-builder-gerbil/install-dependencies.sh

@@ -10,6 +10,7 @@ DEPS=(github.com/fare/gerbil-utils
       github.com/vyzo/gerbil-libp2p
       ) ;
 for i in ${DEPS[@]} ; do
+  echo "Installing gerbil package: $i"
   gxpkg install $i &&
   gxpkg build $i
 done