pom.xml(maven-javadoc-plugin): update to 3.0.0

Changelog:
http://mail-archives.apache.org/mod_mbox/maven-announce/201712.mbox/%3Cop.zaufhhzukdkhrr%40desktop-2khsk44.mshome.net%3E

No functional changes.

Author: php-coder

pom.xml

@@ -514,7 +514,7 @@
 		<!-- Redefine default value from spring-boot-starter-parent (https://github.com/spring-projects/spring-boot/blob/v1.5.7.RELEASE/spring-boot-starters/spring-boot-starter-parent/pom.xml) -->
 		<java.version>1.8</java.version>
 
-		<javadoc.plugin.version>2.10.4</javadoc.plugin.version>
+		<javadoc.plugin.version>3.0.0</javadoc.plugin.version>
 
 		<!-- Redefine default value from spring-boot-dependencies (https://github.com/spring-projects/spring-boot/blob/v1.5.7.RELEASE/spring-boot-dependencies/pom.xml) -->
 		<javax-mail.version>1.5.4</javax-mail.version>