add step-by-step guide for plugin development
display code review and verified status in list

Resolves #23
show comments (and actions) in change detail panel
update documentation files

- add section how to support this plugin
- cleanups
fix remembering self-signed certs for hosts

- fix load logic (trusted hosts will be remembered after restart)
- save authority instead of host only (e.g. host:8080 instead of host)

Related to issue #25
restore Gerrit 2.6 support

- retrieving messages in change details is not supported

Related to issue #25
fix for self signed ssl connections

- fix escaping issues

Resolves issue #25
Merge remote-tracking branch 'origin/master' into intellij13