[MRRESOURCES-91] Avoid overwrite of the destination file if the produced contents is the same

maven-remote-resource-plugin is used in Apache pom to add DEPENDENCIES, and the resulting file is overwritten on each build.
It leads to jar being rebuild, etc leading to longer compilation times.

Patch by Vladimir Sitnikov <sitnikov.vladimir@gmail.com>

This closes #40

git-svn-id: https://svn.apache.org/repos/asf/maven/plugins/trunk@1646543 13f79535-47bb-0310-9956-ffa450edef68
remove redundant configuration

git-svn-id: https://svn.apache.org/repos/asf/maven/plugins/trunk@1646700 13f79535-47bb-0310-9956-ffa450edef68
Verify OS version instead of Java version.
When specifying invoker.javaHome, the Java version of the Maven runtime can be different then the script runtime (which still uses the original runtime aka JAVA_HOME). So use OS, which should be stable.

git-svn-id: https://svn.apache.org/repos/asf/maven/plugins/trunk@1646725 13f79535-47bb-0310-9956-ffa450edef68