To support telling a string is nul-terminated, symbol CURL_ZERO_TERMINATED
has been introduced.
Documentation updated accordingly.
symbols in versions updated. Added form API symbols deprecation info.
This feature is badly supported in Windows: as a replacement, a caller has
to use curl_mime_data_cb() with fread, fseek and possibly fclose
callbacks to process opened files.
The cli tool and documentation are updated accordingly.
The feature is however kept internally for form API compatibility, with
the known caveats it always had.
As a side effect, stdin size is not determined by the cli tool even if
possible and this results in a chunked transfer encoding. Test 173 is
updated accordingly.
