use alpine linux dist for CDT docker

changed to 2.4-alpine:httpd

Change-Id: Ia0335b530bc1a0c08594b3b8800dfb65aac3630b
Issue-ID: APPC-1339
Signed-off-by: Taka Cho <takamune.cho@att.com>
diff --git a/cdt/src/main/docker/Dockerfile b/cdt/src/main/docker/Dockerfile
index caa6ff1..dc2d1ed 100644
--- a/cdt/src/main/docker/Dockerfile
+++ b/cdt/src/main/docker/Dockerfile
@@ -19,10 +19,10 @@
 #
 # ============LICENSE_END============================================
 
-# Base ubuntu with added packages needed for ONAP
-FROM httpd
+# Base Alpine with added packages needed for ONAP
+FROM httpd:2.4-alpine
 MAINTAINER APP-C Team (appc@lists.openecomp.org)
 
 COPY config-design-tool /usr/local/apache2/htdocs/
 
-COPY startCdt.sh /opt
+COPY startCdt.sh /opt/startCdt.sh