OGM-1090 Use Central first to get the artifacts

In passing, remove the sed calls adding this for the Travis build.

Note, I'm using the default Central repository instead of the Google
mirror as apparently a few artifacts are missing on Google mirror.

.travis.yml

@@ -31,10 +31,6 @@ install:
   # The Maven install provided by Travis is outdated, use Maven wrapper to get the latest version
   - mvn -N io.takari:maven:wrapper
   - ./mvnw -v
-  # Use the Google mirror for central - we also declare explicitly central as the JBoss repository takes precedences over it
-  - sed -i settings-example.xml -e "s@</mirrors>@<mirror><id>google-maven-central</id><name>Google Maven Central</name><url>https://maven-central.storage.googleapis.com</url><mirrorOf>central</mirrorOf></mirror></mirrors>@"
-  - sed -i settings-example.xml -e "s@<repositories>@<repositories><repository><id>central</id><name>Central</name><url>https://maven-central.storage.googleapis.com/</url></repository>@"
-  - sed -i settings-example.xml -e "s@<pluginRepositories>@<pluginRepositories><pluginRepository><id>central</id><name>Central</name><url>https://maven-central.storage.googleapis.com/</url></pluginRepository>@"
   # first run to download all the Maven dependencies without logging
   - travis_wait ./mvnw -B -q -s settings-example.xml -Ptest -DskipTests=true -Dmaven.javadoc.skip=true -DskipDistro=true install
   # we run checkstyle first to fail fast if there is a styling error

settings-example.xml

@@ -255,6 +255,16 @@ under the License.
         <profile>
             <id>jboss-public-repository</id>
             <repositories>
+                <!-- Use Central first -->
+                <repository>
+                    <id>central</id>
+                    <name>Maven Central</name>
+                    <url>http://repo.maven.apache.org/maven2/</url>
+                    <snapshots>
+                        <enabled>false</enabled>
+                        <updatePolicy>never</updatePolicy>
+                    </snapshots>
+                </repository>
                 <repository>
                     <id>jboss-public-repository-group</id>
                     <name>JBoss Public Maven Repository Group</name>
@@ -271,6 +281,16 @@ under the License.
                 </repository>
             </repositories>
             <pluginRepositories>
+                <!-- Use Central first -->
+                <pluginRepository>
+                    <id>central</id>
+                    <name>Maven Central</name>
+                    <url>http://repo.maven.apache.org/maven2/</url>
+                    <snapshots>
+                        <enabled>false</enabled>
+                        <updatePolicy>never</updatePolicy>
+                    </snapshots>
+                </pluginRepository>
                 <pluginRepository>
                     <id>jboss-public-repository-group</id>
                     <name>JBoss Public Maven Repository Group</name>