Install a node library from a file

[fdb]

As a step-up to the node store, add a way to install a node library from a .jar file from your local file system.

In addition, also make a simple node library manager available that allows you to list node libraries, add and remove them.

[fdb]

Important: EclipseStarter now starts up with the "-clean" command-line argument. This means that all installed plugins are removed. Remove this flag if you want installed libraries to persist between runs.

[fdb]

A partial implementation exists as of fa32186. This can list loaded libraries and load libraries from disk.