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.
jsondoc-master
jsondoc-core
{groupId='org.slf4j', artifactId='slf4j-log4j12'}
{groupId='log4j', artifactId='log4j'}
{groupId='org.springframework', artifactId='spring-webmvc'}
jsondoc-springmvc
{groupId='org.springframework', artifactId='spring-webmvc'}
{groupId='org.springframework', artifactId='spring-test'}
jsondoc-maven-plugin
{groupId='org.jsondoc', artifactId='jsondoc-springmvc'}
{groupId='org.springframework', artifactId='spring-webmvc'}
{groupId='org.apache.commons', artifactId='commons-io'}
{groupId='junit', artifactId='junit'}
jsondoc-ui
jsondoc-ui-webjar
{groupId='junit', artifactId='junit'}
spring-boot-starter-jsondoc
{groupId='org.springframework.boot', artifactId='spring-boot-starter-web'}
{groupId='org.springframework.boot', artifactId='spring-boot-configuration-processor'}
{groupId='junit', artifactId='junit'}

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