Improve MAVEN build Performance

[ChenZhangg]

Parallel builds in Maven 3 Maven 3.x has the capability to perform parallel builds.

Apache Maven Dependency Plugin can be used to find unused dependencies. And I found following list. Maybe we can remove them. ninja ninja-core {groupId='com.google.inject.extensions', artifactId='guice-assistedinject'} {groupId='org.slf4j', artifactId='jcl-over-slf4j'} {groupId='org.slf4j', artifactId='log4j-over-slf4j'} {groupId='org.hibernate', artifactId='hibernate-validator'} {groupId='com.fasterxml.woodstox', artifactId='woodstox-core'} {groupId='org.flywaydb', artifactId='flyway-core'} {groupId='com.google.inject.extensions', artifactId='guice-persist'} {groupId='org.hibernate', artifactId='hibernate-entitymanager'} {groupId='org.hibernate', artifactId='hibernate-c3p0'} {groupId='org.powermock', artifactId='powermock-module-junit4'} {groupId='org.powermock', artifactId='powermock-api-mockito2'} {groupId='javax.xml.bind', artifactId='jaxb-api'} ninja-postoffice {groupId='org.mockito', artifactId='mockito-core'} ninja-websockets-jsr356 ninja-servlet ninja-standalone {groupId='javax.websocket', artifactId='javax.websocket-api'} ninja-db-classic ninja-test-utilities {groupId='org.ninjaframework', artifactId='ninja-standalone'} {groupId='org.hamcrest', artifactId='java-hamcrest'} {groupId='org.seleniumhq.selenium', artifactId='htmlunit-driver'} {groupId='org.eclipse.jetty', artifactId='jetty-client'} {groupId='org.eclipse.jetty.websocket', artifactId='websocket-client'} ninja-jaxy-routes {groupId='org.ninjaframework', artifactId='ninja-test-utilities'} ninja-metrics ninja-metrics-graphite ninja-metrics-ganglia {groupId='junit', artifactId='junit'} {groupId='org.mockito', artifactId='mockito-core'} ninja-metrics-librato {groupId='junit', artifactId='junit'} {groupId='org.mockito', artifactId='mockito-core'} ninja-metrics-influxdb {groupId='junit', artifactId='junit'} {groupId='org.mockito', artifactId='mockito-core'} ninja-maven-plugin {groupId='org.apache.maven', artifactId='maven-compat'} ninja-servlet-integration-test {groupId='org.webjars', artifactId='bootstrap'} {groupId='org.mindrot', artifactId='jbcrypt'} ninja-servlet-jpa-blog-integration-test {groupId='org.webjars', artifactId='tinymce-jquery'} {groupId='org.webjars', artifactId='bootstrap'} {groupId='com.h2database', artifactId='h2'} {groupId='org.ninjaframework', artifactId='ninja-servlet'} ninja-servlet-jpa-blog-archetype ninja-servlet-archetype-simple

===================== If there are any inappropriate modifications in this PR, please give me a reply and I will change them.