plugin: README.md updates (#1084)

updates so the look better on coredns.io

plugin/autopath/README.md

 # autopath
 
-The *autopath* plugin allows CoreDNS to perform server side search path completion.
-If it sees a query that matches the first element of the configured search path, *autopath* will
-follow the chain of search path elements and returns the first reply that is not NXDOMAIN.
-On any failures the original reply is returned.
+*autopath* allows CoreDNS to perform server side search path completion.
 
-Because *autopath* returns a reply for a name that wasn't the original question it will add a CNAME
-that points from the original name (with the search path element in it) to the name of this answer.
+If it sees a query that matches the first element of the configured search path, *autopath* will
+follow the chain of search path elements and returns the first reply that is not NXDOMAIN. On any
+failures the original reply is returned. Because *autopath* returns a reply for a name that wasn't
+the original question it will add a CNAME that points from the original name (with the search path
+element in it) to the name of this answer.
 
 ## Syntax
 

plugin/chaos/README.md

 # chaos
 
-The *chaos* plugin allows CoreDNS to respond to TXT queries in the CH class.
+*chaos* allows CoreDNS to respond to TXT queries in the CH class.
 
 This is useful for retrieving version or author information from the server.
 

plugin/erratic/README.md

 # erratic
 
-*erratic* is a plugin useful for testing client behavior. It returns a static response to all
-queries, but the responses can be delayed, dropped or truncated.
+*erratic* is a plugin useful for testing client behavior.
 
+It returns a static response to all queries, but the responses can be delayed, dropped or truncated.
 The *erratic* plugin will respond to every A or AAAA query. For any other type it will return
 a SERVFAIL response. The reply for A will return 192.0.2.53 (see RFC 5737), for AAAA it returns
 2001:DB8::53 (see RFC 3849).
 
 *erratic* can also be used in conjunction with the *autopath* plugin. This is mostly to aid in
- testing.
+testing.
 
 ## Syntax
 

plugin/federation/README.md

 # federation
 
-The *federation* plugin enables
+*federation* enables
 [federated](https://kubernetes.io/docs/tasks/federation/federation-service-discovery/) queries to be
 resolved via the kubernetes plugin.
 

plugin/health/README.md

 # health
 
-This module enables a simple health check endpoint. By default it will listen on port 8080.
+*health* enabless a simple health check endpoint. By default it will listen on port 8080.
 
 ## Syntax
 

plugin/kubernetes/README.md

 # kubernetes
 
-The *kubernetes* plugin enables the reading zone data from a Kubernetes cluster.  It implements
-the [Kubernetes DNS-Based Service Discovery
+The *kubernetes* plugin enables the reading zone data from a Kubernetes cluster.
+
+It implements the [Kubernetes DNS-Based Service Discovery
 Specification](https://github.com/kubernetes/dns/blob/master/docs/specification.md).
 
 CoreDNS running the kubernetes plugin can be used as a replacement of kube-dns in a kubernetes

plugin/metrics/README.md

 # prometheus
 
-This module enables prometheus metrics for CoreDNS.
+*prometheus* enables [Prometheus](https://prometheus.io/) metrics for CoreDNS.
 
 The default location for the metrics is `localhost:9153`. The metrics path is fixed to `/metrics`.
 The following metrics are exported:

plugin/pprof/README.md

 # pprof
 
-*pprof* publishes runtime profiling data at endpoints under /debug/pprof.
+*pprof* publishes runtime profiling data at endpoints under `/debug/pprof`.
 
 You can visit `/debug/pprof` on your site for an index of the available endpoints. By default it
 will listen on localhost:6053.

plugin/reverse/README.md

 # reverse
 
-The *reverse* plugin allows CoreDNS to respond dynamically to a PTR request and the related A/AAAA request.
+*reverse* allows CoreDNS to respond dynamically to a PTR request and the related A/AAAA request.
 
 ## Syntax
 
@@ -38,7 +38,7 @@ The zone will be matched by the zones listed in *this* configuration stanza.
 
 ## Examples
 
-~~~ txt
+~~~ corefile
 arpa compute.internal {
     # proxy unmatched requests
     proxy . 8.8.8.8
@@ -63,7 +63,7 @@ arpa compute.internal {
 ~~~
 
 
-~~~ txt
+~~~ corefile
 32.10.in-addr.arpa.arpa arpa.company.org {
 
     reverse 10.32.0.0/16 {

plugin/trace/README.md

 # trace
 
-This module enables OpenTracing-based tracing of DNS requests as they go through the
-plugin chain.
+*trace* enables OpenTracing-based tracing of DNS requests as they go through the plugin chain.
 
 ## Syntax