Use topic name to compute the collection to send the updates in "Standard Solr"

[didiez]

In "Standard Solr" mode, there is no way to route messages dynamically to multiple collections using RegexRouter as noted in the docs.

HttpSolrSinkTask should use topic to send the documents to a solr collection with that very same name.
Either appending the collection to the base solrUrl in ...

kafka-connect-solr/src/main/java/com/github/jcustenborder/kafka/connect/solr/HttpSolrSinkTask.java

Line 42 in c917b5c

SolrClient client(String topic) {

Or using the overloaded method process(SolrClient client, String collection) in

kafka-connect-solr/src/main/java/com/github/jcustenborder/kafka/connect/solr/HttpSolrSinkTask.java

Line 56 in c917b5c

UpdateResponse response = updateRequest.process(client);