Use repo.maven.com instead of archive.apache.org to get mvn for Travis

archive.apache.org had a 5G daily download limit per IP

Author: tbarsballe

.travis.yml

@@ -11,7 +11,7 @@ env:
   global:
     - MAVEN_OPTS=-Xmx512m
 before_script:
-  - wget https://archive.apache.org/dist/maven/maven-3/3.5.0/binaries/apache-maven-3.5.0-bin.tar.gz
+  - wget https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.5.0/apache-maven-3.5.0-bin.tar.gz
   - tar zxf apache-maven-3.5.0-bin.tar.gz
   - export M2_HOME=$PWD/apache-maven-3.5.0
   - export PATH=$M2_HOME/bin:$PATH