Improve documentation

Signed-off-by: chirsz-ever <chirsz@foxmail.com>

README.md

@@ -1767,7 +1767,7 @@ However, you can set set parameter `ignore_comments` to true in the `parse` func
 
 ### Trailing commas
 
-Trailing commas in arrays and objects are also not part of the [JSON specification](https://tools.ietf.org/html/rfc8259), and this library does not support it by default.
+The JSON specification does not allow trailing commas in arrays and objects, and hence this library is treating them as parsing errors by default.
 
 Like comments, you can set parameter `ignore_trailing_commas` to true in the `parse` function to ignore trailing commas in arrays and objects. Note that a single comma as the only content of the array or object (`[,]` or `{,}`) is not allowed, and multiple trailing commas (`[1,,]`) are not allowed either.
 

docs/mkdocs/docs/api/basic_json/accept.md

@@ -53,7 +53,7 @@ Unlike the [`parse()`](parse.md) function, this function neither throws an excep
     (`#!cpp false`); (optional, `#!cpp false` by default)
 
 `ignore_trailing_commas` (in)
-:   whether trailing commas in arrays or objects should be allowed (`#!cpp true`) or yield a parse error
+:   whether trailing commas in arrays or objects should be ignored and treated like whitespace (`#!cpp true`) or yield a parse error
     (`#!cpp false`); (optional, `#!cpp false` by default)
 
 `first` (in)

docs/mkdocs/docs/api/basic_json/parse.md

@@ -59,7 +59,7 @@ static basic_json parse(IteratorType first, IteratorType last,
     (`#!cpp false`); (optional, `#!cpp false` by default)
 
 `ignore_trailing_commas` (in)
-:   whether trailing commas in arrays or objects should be allowed (`#!cpp true`) or yield a parse error
+:   whether trailing commas in arrays or objects should be ignored and treated like whitespace (`#!cpp true`) or yield a parse error
     (`#!cpp false`); (optional, `#!cpp false` by default)
 
 `first` (in)

docs/mkdocs/docs/api/basic_json/sax_parse.md

@@ -68,7 +68,7 @@ The SAX event lister must follow the interface of [`json_sax`](../json_sax/index
     (`#!cpp false`); (optional, `#!cpp false` by default)
 
 `ignore_trailing_commas` (in)
-:   whether trailing commas in arrays or objects should be allowed (`#!cpp true`) or yield a parse error
+:   whether trailing commas in arrays or objects should be ignored and treated like whitespace (`#!cpp true`) or yield a parse error
     (`#!cpp false`); (optional, `#!cpp false` by default)
 
 `first` (in)