fix spelling mistakes (#3202)

Signed-off-by: hwdef <hwdef97@gmail.com>

notes/coredns-004.md

@@ -24,7 +24,7 @@ We are now also releasing an ARM build that can run on Raspberry Pi.
 * *file|auto*: include zone's NSset in positive responses.
 * *auto*: close files and don't leak file descriptors.
 * *httpproxy*: new plugin that proxies to <https://dns.google.com> and resolves your requests over an encrypted connection. This plugin will probably be morphed into proxy at some point in the feature. Consider it experimental for the time being.
-* *metrics*: `reponse_size_bytes` and `request_size_bytes` export the actual length of the packet, not the advertised bufsize.
+* *metrics*: `response_size_bytes` and `request_size_bytes` export the actual length of the packet, not the advertised bufsize.
 * *log*: `{size}` is now the length in bytes of the request, `{rsize}` for the reply. Default logging is changed to show both.
 
 # Contributors

notes/coredns-1.0.2.md

@@ -9,7 +9,7 @@ author = "coredns"
 +++
 
 We are pleased to announce the [release](https://github.com/coredns/coredns/releases/tag/v1.0.2) of CoreDNS-1.0.2!
-This release can be summerized as "help external plugin developers" as most changes are geared
+This release can be summarized as "help external plugin developers" as most changes are geared
 towards exposing CoreDNS functionality to make this as easy as possible. Is also a fairly small
 release.