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.
This patch improves the output of curl's --libcurl option by
generating code which builds curl_httppost and curl_slist lists, and
uses symbolic names for enum and flag values. Variants of the
my_setopt macro in tool_setopt.h are added in order to pass extra type
information to the code-generation step in tool_setopt.c.
If curl is configured with --disable-libcurl-option then the macros
call curl_easy_setopt directly.
