drop 'learn-mac-based-vlan' and 'manage-umts'

This was undocumented and scripts did never catch up with general
quality expectations, for example global-config and global functions
were not used.
If you need the code get it from git history. 😜

Author: eworm-de

README.md

@@ -206,10 +206,6 @@ Available scripts
 * [Update GRE configuration with dynamic addresses](doc/update-gre-address.md)
 * [Update tunnelbroker configuration](doc/update-tunnelbroker.md)
 
-[comment]: # (TODO: currently undocumented)
-[comment]: # (* learn-mac-based-vlan)
-[comment]: # (* manage-umts)
-
 Available modules
 -----------------