QDataStream docs give wrong examples

Reading the latest QDataStream docs from doc-snapshots, I still see that it mentions incorrect serialization formats here and there.

For example:

To take one example, a char * string is written as a 32-bit integer equal to the length of the string including the '\0' byte, followed by all the characters of the string including the '\0' byte. When reading a char * string, 4 bytes are read to create the 32-bit length value, then that many characters for the char * string including the '\0' terminator are read.

This is only correct if the string size fits into 32 bits.
The current code for serializing a const char * string is more complicated, and contains the same logic as other string/container serialization.

The scope of this task is to find all such places in QDataStream documentation and fix them.