improve service manager

- do not start sea server automatically
- replace _SERVICE in FRAPPY_HISTORY by service name
- imporve error messages
- no fiddling around with sys,path, reply on PYTHONPATH for
  finding packages

bin/seweb

@@ -23,10 +23,6 @@
 
 import sys
 from os.path import join, abspath, dirname
-
-# for packages: servicemanager, frappyhistory
-sys.path.insert(0, abspath(join(dirname(__file__), '../..')))
-
 from servicemanager import run
 
 run('seweb', sys.argv[1:])