Plug storagemanager config file into build system

The storagemanager.cnf still has the default for its storage at $HOME/storagemanager. That should be parameterized, and generated by cmake. For default installations it should be /var/lib/columnstore/storagemanager.

Upgrades shouldn't be affected because we currently copy their old configuration to their new configuration. Presumably, whatever they are currently using is fine with them.