Better handling of failed downloads

Switched to newer version of the download plugin which fails on
incomplete downloads. Disabled cache polling for large server ZIP file
and enabled overwriting of the target file.

Author: ngrigoriev

pom.xml

@@ -28,7 +28,7 @@
         <maven.failsafe.version>2.19.1</maven.failsafe.version>
         <maven.resources.plugin.version>2.7</maven.resources.plugin.version>
         <exec.maven.plugin.version>1.2</exec.maven.plugin.version>
-        <download.maven.plugin.version>1.2.1</download.maven.plugin.version>
+        <download.maven.plugin.version>1.3.0</download.maven.plugin.version>
         <slf4j.version>1.7.21</slf4j.version>
         <opencsv.version>3.8</opencsv.version>
         <metrics3.version>3.0.1</metrics3.version>
@@ -445,7 +445,9 @@
                                 <configuration>
                                     <url>https://github.com/JanusGraph/janusgraph/releases/download/v${janusgraph.version}/janusgraph-${janusgraph.version}-hadoop2.zip</url>
                                     <unpack>false</unpack>
-                                    <outputDirectory>${project.build.directory}/../server</outputDirectory>
+				    <outputDirectory>${project.build.directory}/../server</outputDirectory>
+				    <skipCache>true</skipCache>
+				    <overwrite>true</overwrite>
                                 </configuration>
                             </execution>
                         </executions>