Revert fix_mxclient_symlink fixing

This reverts commit 41337504dc96a05f0e66e98d96c409ed73848916.

Instead of duct taping this error, it should be fixed in a more
structural way.
Remove 'not to be used' module imports, add munin
m2ee.py import cosmetics
Move mxclientsystem symlink handling back to start

This fixes a bug introduced in bcead2e43387c4d1c239053b00cf687a5169eacb.

Moving fix_symlink from core to unpack was a bad idea, because it
fails really hard when unpacking an mda, while the associated runtime
is not present.

Now, the symlink will be set when starting the application, like it was
before.
fix_mxclientsystem_symlink: cosmetics and logging
rename m2ee->cli to prevent name collision
Add m2ee version number indication

display version information when starting (debug-level) and in about
output
cli: abort when send runtime configuration fails
Remove unnecessary imports

munin and nagios are now imported in __init__ of m2ee, and m2ee is
imported into the namespace already
update TODO