doc update (#1140)

* doc update

Go through all README and fix mistakes, extend example and let more
corefile snippets be test for validity.

* Cant use spefic addr in test

plugin/pprof/README.md

@@ -6,7 +6,7 @@ You can visit `/debug/pprof` on your site for an index of the available endpoint
 will listen on localhost:6053.
 
 > This is a debugging tool. Certain requests (such as collecting execution traces) can be slow. If
-> you use pprof on a live site, consider restricting access or enabling it only temporarily.
+> you use pprof on a live server, consider restricting access or enabling it only temporarily.
 
 For more information, please see [Go's pprof
 documentation](https://golang.org/pkg/net/http/pprof/) and read
@@ -25,12 +25,14 @@ If not specified, ADDRESS defaults to localhost:6053.
 Enable pprof endpoints:
 
 ~~~
-pprof
+. {
+    pprof
+}
 ~~~
 
 Listen on an alternate address:
 
-~~~
+~~~ txt
 . {
     pprof 10.9.8.7:6060
 }
@@ -38,6 +40,8 @@ Listen on an alternate address:
 
 Listen on an all addresses on port 6060:
 
-~~~
-pprof :6060
+~~~ txt
+. {
+    pprof :6060
+}
 ~~~