Fix contradictions between the documentation, the README, and the library (#5825)

- Discarded values: the legacy macro only changes <= and >=; != is true by default
- Out-of-range numbers are rejected while parsing, not stored as NaN
- merge_diff round trip: point to the ordered_json caveat
- ensure_ascii example shows the escaped output
- out_of_range.405 is thrown for "remove"/"move" on the root, not "add"
- CBOR stores binary subtypes as tags
- Integer/float comparison uses exact values, not conversion
- diff, flatten, and the binary writers are depth-bounded
- FAQ: max_digits10 for serialization, trailing commas are supported
- out_of_range.407 is still thrown by to_bon8
- FetchContent_MakeAvailable needs CMake 3.14
- json_fwd.hpp contents, operator< link, RFC 7396 for merge patch
- README: dump() wording, merge_diff, MSYS2/build2, patch comment typos,
  operator[] link, embedded CMake example aligned with the docs

Signed-off-by: Niels Lohmann <mail@nlohmann.me>

docs/mkdocs/docs/integration/cmake.md

@@ -90,13 +90,13 @@ to the following.
 
 ### FetchContent
 
-Since CMake v3.11, [FetchContent](https://cmake.org/cmake/help/v3.11/module/FetchContent.html) can be used to
+Since CMake v3.14, [FetchContent](https://cmake.org/cmake/help/v3.14/module/FetchContent.html) can be used to
 automatically download a release as a dependency at configure time.
 
 !!! example
 
     ```cmake title="CMakeLists.txt"
-    cmake_minimum_required(VERSION 3.11)
+    cmake_minimum_required(VERSION 3.14)
     project(ExampleProject LANGUAGES CXX)
 
     include(FetchContent)