fixes #7
adds more frequent checks for dead servers

- fixes class hierarchy
- handles check interval in milliseconds
[maven-release-plugin] prepare release v0.1.1
[maven-release-plugin] prepare for next development iteration
fixes typo
moves predicates into SolrServerWrapper
introduces NoAliveSolrServerLeftException
fixes pre-configured configuration

- configuration now in spring factory bean style. this is more reliable in spring ioc container
introduces parallel checks && request wait for next alive server

- solr alive checks are executed in parallel – if a multi threaded executor service is supplied
- requests wait for a configurable amount for any solr server to become alive again
[maven-release-plugin] prepare release v0.1.2
[maven-release-plugin] prepare for next development iteration
Merge remote-tracking branch 'upstream/master' into integration-tests
Fix compilation errors after merge from upstream.
Shutdown httpClient in IT as this is no longer done by the FLHSS