Pull request: 3184 disable private ptr

Merge in DNS/adguard-home from 3184-disable-ptr to master

Updates #3184.

Squashed commit of the following:

commit b78ac2eeb1b408586808ddbd1c87107f373b11b0
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Wed May 26 17:20:34 2021 +0300

    all: rename dns config field

commit 36512134822a5f6b8b296ccbd7e7d5a9b8e87f26
Author: Ildar Kamalov <ik@adguard.com>
Date:   Wed May 26 15:55:44 2021 +0300

    client: handle local ips rdns

commit 9a691830d45db93e078332d85bc0efa7dc7b6ac6
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Wed May 26 14:43:13 2021 +0300

    all: imp naming

commit 771b7a3d5d25f91408dd97ba3287efb641028ccf
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Wed May 26 14:24:38 2021 +0300

    all: imp docs, code

commit be960893e8bbb7375a944ca0345b50c857a2d7cf
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Wed May 26 13:23:56 2021 +0300

    all: imp docs & log changes

commit 4e645a520f6bb584ef951435ee833ad30769af98
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Wed May 26 12:49:44 2021 +0300

    all: add the field into structs

commit 22b5b6163f086560a3189234532ba877be7ba940
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Tue May 25 15:10:31 2021 +0300

    dnsforward: entitle lock, imp code

CHANGELOG.md

@@ -15,6 +15,8 @@ and this project adheres to
 
 ### Added
 
+- The ability to completely disable reverse DNS resolving of IPs from
+  locally-served networks ([#3184]).
 - New flag `--local-frontend` to serve dinamically changeable frontend files
   from disk as opposed to the ones that were compiled into the binary.
 
@@ -35,6 +37,8 @@ released by then.
 
 - Go 1.15 support.
 
+[#3184]: https://github.com/AdguardTeam/AdGuardHome/issues/3184
+
 
 
 ## [v0.106.3] - 2021-05-19