Also, use memset() instead of a lame loop.
The previous logic that tried to avoid too many updates were very
ineffective for really fast transfers, as then it could easily end up
doing hundreds of updates per second that would make a significant
impact in transfer performance!
Bug: http://curl.haxx.se/mail/archive-2013-07/0031.html
Reported-by: Marc Doughty
Configuration files such as curl_config.h and all config-*.h no longer exist
nor are generated/copied into 'src' directory, now these only exist in 'lib'
directory from where curl tool sources uses them.
Additionally old src/setup.h has been refactored into src/tool_setup.h which
now pulls lib/setup.h
The possibility of a makefile needing an include path adjustment exists.
Daniel Stenberg