Add has_servers() method to MemcachedStore to allow validity checking
Add error log if cluster_settings file becomes invalid after startup
Easier tailing of log files
Call Diversion AS
Merge pull request #189 from rkday/memcached_has_servers

Add extra validity checking to MemcachedStore
Merge pull request #190 from rkday/log_tailing

Easier tailing of log files
Merge pull request #192 from Metaswitch/sto985

[Reviewer: Andy] Call Diversion AS