docker: pass proxy arguments to docker process

Building in Docker when behind a proxy requires passing the proxy variables.

Differential Revision: https://phab.mercurial-scm.org/D190

contrib/dockerlib.sh

@@ -38,5 +38,5 b' function initcontainer() {'
         echo RUN groupadd $DBUILDUSER -g `id -g` -o
         echo RUN useradd $DBUILDUSER -u `id -u` -g $DBUILDUSER -o
     fi
-  ) | $DOCKER build --tag $CONTAINER -
+  ) | $DOCKER build --build-arg http_proxy --build-arg https_proxy --tag $CONTAINER -
 }

contrib/dockerrpm

@@ -16,10 +16,10 b' RPMBUILDDIR=$ROOTDIR/packages/$PLATFORM'
 contrib/buildrpm --rpmbuilddir $RPMBUILDDIR --prepare $*
 
 DSHARED=/mnt/shared
-$DOCKER run -u $DBUILDUSER --rm -v $RPMBUILDDIR:$DSHARED $CONTAINER \
+$DOCKER run -e http_proxy -e https_proxy -u $DBUILDUSER --rm -v $RPMBUILDDIR:$DSHARED $CONTAINER \
     rpmbuild --define "_topdir $DSHARED" -ba $DSHARED/SPECS/mercurial.spec --clean
 
-$DOCKER run -u $DBUILDUSER --rm -v $RPMBUILDDIR:$DSHARED $CONTAINER \
+$DOCKER run -e http_proxy -e https_proxy -u $DBUILDUSER --rm -v $RPMBUILDDIR:$DSHARED $CONTAINER \
     createrepo $DSHARED
 
 cat << EOF > $RPMBUILDDIR/mercurial.repo