mdbx: release v0.11.2

Acknowledgements:
-----------------

 - [장세연 (Чан Се Ен)](https://github.com/sasgas) for contributing to C++ API.
 - [Alain Picard](https://github.com/castortech) for [Java bindings](https://github.com/castortech/mdbxjni).
 - [Alex Sharov](https://github.com/AskAlexSharov) for reporting and testing.
 - [Kris Zyp](https://github.com/kriszyp) for reporting and testing.
 - [Artem Vorotnikov](https://github.com/vorot93) for support [Rust wrapper](https://github.com/vorot93/libmdbx-rs).

Fixes:
------

 - [Fixed compilation](#239) with `devtoolset-9` on CentOS/RHEL 7.
 - [Fixed unexpected `MDBX_PROBLEM` error](#242) because of update an obsolete meta-page.
 - [Fixed returning `MDBX_NOTFOUND` error](#243) in case an inexact value found for `MDBX_GET_BOTH` operation.
 - [Fixed compilation](#245) without kernel/libc-devel headers.

Minors:
-------

 - Fixed `constexpr`-related macros for legacy compilers.
 - Allowed to define 'CMAKE_CXX_STANDARD` using an environment variable.
 - Simplified collection statistics of page operation .
 - Added `MDBX_FORCE_BUILD_AS_MAIN_PROJECT` cmake option.
 - Remove unneeded `#undef P_DIRTY`.

Signed-off-by: Леонид Юрьев (Leonid Yuriev) <leo@yuriev.ru>

ChangeLog.md

@@ -18,7 +18,7 @@ ChangeLog
  - Packages for [Astra Linux](https://astralinux.ru/), [ALT Linux](https://www.altlinux.org/), [ROSA Linux](https://www.rosalinux.ru/), etc.
 
 
-## v0.11.2 (underway, release scheduled for 2021-12-02)
+## v0.11.2 at 2021-12-02
 
 Acknowledgements:
 

appveyor.yml

@@ -1,4 +1,4 @@
-version: 0.11.1.{build}
+version: 0.11.2.{build}
 
 environment:
   matrix: