Updates to registration token

Updated registration token
Added ability to fetch new tokens from remote host
Cache fetched tokens if they work and use in future
Moved useragent and token declaration to constants
Added --ignorecached switch to yowsup-cli to ignore cached tokens
Fixed error on printing some currency codes
Updates to options

Removed --v1 switch
Removed dbus option until it's properly tested and documented
Merge branch 'master' of https://github.com/tgalal/yowsup