Update the Unicode support FAQ documentation

Author: stephen-webb

src/site/markdown/faq.md

@@ -47,12 +47,26 @@ DLL" with release builds of Log4cxx and "Multithread DLL Debug" with debug build
 Yes. Apache Log4cxx exposes API methods in multiple string flavors supporting differently encoded
 textual content, like `char*`, `std::string`, `wchar_t*`, `std::wstring`, `CFStringRef` et al. All
 provided texts will be converted to the `LogString` type before further processing, which is one of
-several supported Unicode representations selected by the `LOG4CXX_CHAR` cmake option. If methods are
+several supported internal representations and is selected by the `LOG4CXX_CHAR` cmake option. If methods are
 used that take `LogString` as arguments, the macro `LOG4CXX_STR()` can be used to convert literals
-to the current `LogString` type. FileAppenders support an encoding property as well, which should be
-explicitly specified to `UTF-8` or `UTF-16` for e.g. XML files. The important point is to get the
-chain of input, internal processing and output correct and that might need some additional setup in
-the app using Log4cxx:
+to the current `LogString` type. 
+
+The default external representation is controlled by the `LOG4CXX_CHARSET` cmake option.
+FileAppenders support an `Encoding` property allowing character set encoding control per appender.
+For example, you can use `UTF-8` or `UTF-16` when writing XML or JSON layouts.
+Log4cxx also implements character set encodings for `US-ASCII` (`ISO646-US` or `ANSI_X3.4-1968`)
+and `ISO-8859-1` (`ISO-LATIN-1` or `CP1252`).
+You are highly encouraged to stick to `UTF-8` for the best support from tools, API and operating systems.
+
+The `locale` character set encoding provides support beyond the above internally implemented options.
+It allows you to use any multi-byte encoding provided by the standard library.
+See also [some SO post](https://stackoverflow.com/questions/571359/how-do-i-set-the-proper-initial-locale-for-a-c-program-on-windows)
+on setting the default locale in C++.
+
+```
+std::setlocale( LC_ALL, "" ); /* Set locale for C functions */
+std::locale::global(std::locale("")); /* set locale for C++ functions */
+```
 
 According to the [libc documentation](https://www.gnu.org/software/libc/manual/html_node/Setting-the-Locale.html),
 all programs start in the `C` locale by default, which is the [same as ANSI_X3.4-1968](https://stackoverflow.com/questions/48743106/whats-ansi-x3-4-1968-encoding)
@@ -72,13 +86,5 @@ loggername - ?????????? ???? ??????????????
 The important thing to understand is that this is some always applied, backwards compatible default
 behaviour and even the case when the current environment sets a locale like `en_US.UTF-8`. One might
 need to explicitly tell the app at startup to use the locale of the environment and make things
-compatible with Unicode this way. See also [some SO post](https://stackoverflow.com/questions/571359/how-do-i-set-the-proper-initial-locale-for-a-c-program-on-windows)
-on setting the default locale in C++.
-
-```
-std::setlocale( LC_ALL, "" ); /* Set locale for C functions */
-std::locale::global(std::locale("")); /* set locale for C++ functions */
-```
+compatible with Unicode this way.
 
-See [LOGCXX-483](https://issues.apache.org/jira/browse/LOGCXX-483) or [GHPR #31](https://github.com/apache/logging-log4cxx/pull/31#issuecomment-668870727)
-for additional details.