Fix typo in exporter names

This patch fixes some typos in project names:

- “Elasticsearch” which was written with an uppercase `S`, while the
  product is written with a lowercase `s` (see:
  https://www.elastic.co/elasticsearch/).

- “MinIO” which was written with a lowercase “io” while it should be
  uppercase (see: https://min.io/)

Signed-off-by: Lars Kiesow <lkiesow@uos.de>

Author: lkiesow

content/docs/instrumenting/exporters.md

@@ -36,7 +36,7 @@ wide variety of JVM-based applications, for example [Kafka](http://kafka.apache.
    * [Couchbase exporter](https://github.com/blakelead/couchbase_exporter)
    * [CouchDB exporter](https://github.com/gesellix/couchdb-exporter)
    * [Druid Exporter](https://github.com/opstree/druid-exporter)
-   * [ElasticSearch exporter](https://github.com/justwatchcom/elasticsearch_exporter)
+   * [Elasticsearch exporter](https://github.com/justwatchcom/elasticsearch_exporter)
    * [EventStore exporter](https://github.com/marcinbudny/eventstore_exporter)
    * [IoTDB exporter](https://github.com/fagnercarvalho/prometheus-iotdb-exporter)
    * [KDB+ exporter](https://github.com/KxSystems/prometheus-kdb-exporter)
@@ -278,7 +278,7 @@ separate exporters are needed:
    * [mgmt](https://github.com/purpleidea/mgmt/blob/master/docs/prometheus.md)
    * [MidoNet](https://github.com/midonet/midonet)
    * [midonet-kubernetes](https://github.com/midonet/midonet-kubernetes) (**direct**)
-   * [Minio](https://docs.minio.io/docs/how-to-monitor-minio-using-prometheus.html)
+   * [MinIO](https://docs.minio.io/docs/how-to-monitor-minio-using-prometheus.html)
    * [Netdata](https://github.com/firehol/netdata)
    * [Pretix](https://pretix.eu/)
    * [Quobyte](https://www.quobyte.com/) (**direct**)