Don't bundle the stacks.yaml for the fuse runtime in server adapter but use remote one

Currently the fuse.yaml is bundled inside the server adapter plugin. This has the backdraw that we can't make changes once the plugin is shipped / released.

The other JBoss tooling is using a remote stacks.yaml file which can be changed at any time and gets picked up by all users directly as it is loaded from the internet instead of being bundled in the plugin. Thus it is more flexible if we need to push changes or additions to the file.

We should move the JBoss Fuse stacks.yaml file out of the server adapter plugin and add it to the remote one. Once JBoss Fuse 6.2 is available from the download portal we can easily push a change to that remote file and the download will be accessable by all users. That applies also to new follow up versions of JBoss Fuse like 6.2.1 for instance which then don't need a new build of the tooling server adapter plugin to appear in the available runtimes.