Multiple versions

Support for multiple versions. Currently there are 1.0.0-RC1 and 0.90.11 (both locally compiled).

What this commit did:
- moved usr/ to versions/<version>/
- added versions/0.90.11-SNAPSHOT/
- changed manifest.yml in order to support multiple versions (version string can't contain suffix '-SNAPSHOT')
- ES config file is set in $ES_JAVA_OPTS
- handle dns timeouts on publish-unicast-host