Disable memory checking on dist'd builds (#15)

Gets rid of the following message (as well as any performance penalties we may be paying):

> WARN: Strict java memory checking is enabled, don't do release builds or performance runs with this enabled. Invoke "ant clean" and "ant -Djmemcheck=NO_MEMCHECK" to disable.

I've confirmed this by running the prior release locally.

.circleci/config.yml

@@ -28,7 +28,7 @@ jobs:
       - run: apt-get install -y openjdk-8-jdk-headless ant build-essential cmake python git
       - checkout
       - run: ant clean
-      - run: ant dist
+      - run: ant -Djmemcheck=NO_MEMCHECK dist
       - run: cp obj/release/voltdb-community-*.tar.gz obj/release/mode-voltdb-community.tar.gz
       - store_artifacts:
           path: obj/release/mode-voltdb-community.tar.gz
@@ -98,7 +98,7 @@ commands:
             apt-key fingerprint 0EBFCD88
             add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
             apt-get update
-            apt-get install docker-ce-cli
+            apt-get install -y docker-ce-cli
       - checkout
       - setup_remote_docker:
           docker_layer_caching: true

.circleci/docker/Dockerfile

@@ -15,7 +15,7 @@ WORKDIR /opt/voltdb
 COPY . .
 
 RUN ant clean
-RUN ant dist | ts '[%Y-%m-%d %H:%M:%S]'
+RUN ant -Djmemcheck=NO_MEMCHECK dist | ts '[%Y-%m-%d %H:%M:%S]'
 RUN cp obj/release/voltdb-community-*.tar.gz obj/release/voltdb-community.tar.gz