#56 configuration: Sweep 9.1 -> 9.0 causes config problems

[Slawek Mikula]

Inital:
- Ubuntu Dapper Drake
- sweep 9.1 compiled by hand (usr/local)
- everything went fine

Steps:
- upgrade to Ubuntu Edgy Eft
- Sweep 9.0 in default repositories
- installed 9.0 from universe repository

Error:
- sweep loads fine
- playback doesn't work (error with /dev/dsp)
- recording results with square wave (?) recorded

Solution:
- delete all config in ~/.sweep
- re-run application

Error description and possible solution:
- config format changed between 9.0 and 9.1. Dumping version down causes error. Maybe some kind of config versioning could be applied. Main problem is with no visible information about config file incompatibilites.