Support 5.3 apps

[joshmoore]

For apps that need to perform imports, the current logic is faulty since omego will download latest. However, the compose environment variables are not available to the docker script. This changes works around the issue but is not ideal:

[jamoore@idr1-slot2 .omero]$ git diff
diff --git a/docker b/docker
index 86c0b58..c053d51 100755
--- a/docker
+++ b/docker
@@ -115,7 +115,8 @@ install() {
 }

 java() {
-    $ACTION docker exec -e USER_AGENT=Travis -u root $CID /opt/omero/omego/bin/omego download java --sym /opt/omero/java
+    . .omero/.env
+    $ACTION docker exec -e USER_AGENT=Travis -u root $CID /opt/omero/omego/bin/omego download java --release ${OMERO_SERVER_VERSION} -
     $ACTION docker exec $CID ln -s /opt/omero/java/libs /opt/omero/web/OMERO.web/lib/client
 }