Fix for issue 201 of original SoCo (https://github.com/SoCo/SoCo/issues/201)
Checks that the SSDP search response contains the "Sonos" string, otherwise keep waiting for more responses.
Added a very simple example program that only displays the available players. This permits to test the zone discovery algorithm.
Clarified comments as requested.
Added sample Sonos SSDP response
A few adjustments to please pylint
Fixed formatting issue
More lint fixes
Removed useless else statement
More lint massaging...
Fixed unit test for discovery
Corrected timeout behaviour
Removed whitespace for lint
Reduced timeout in select call
Fixed unit test
Merge pull request #202 from gpothier/master

Fix for issue 201. Closes #201.  Thanks for your persistence.