Cross-check plugin versions from directory, buildversion.txt and JVM-compiled code.

[vinjana]

In function LibrariesFactory.loadPluginsFromDirectories do not only read the directory-based version but also the versions from the buildversion.txt and retrieve the built version from the JVM-compiled BasePlugin-subclass, and cross-check that they are compatible (not necessarily identical?).

[vinjana]

Problem for JVM-compiled code. de.dkfz.roddy.plugins.ClassLoaderHelper#searchForClass loads the JAR files, but with a hand-crafted approach. The BasePlugin classes (usually 1; possibly multiple!) are not known from the manifest, so they would have to be searched first. Only then the we could call String BasePlugin.getVersionInfo()