adjusted to the new dns cache function to hide more hostip internals

Don't call the lock/unlock functions if they are NULL. They can still be
NULL without violating protocol.

Dan Fandrich's cleanup patch to make pedantic compiler options cause less
warnings. Minor edits by me.

updated year in the copyright string

the new cookie functions that require 'data' passed in

Dirk Manske's bugfix for the share stuff

Dirk Manske's patch that introduces cookie support to the share interface.

use CURLDEBUG instead of MALLOCDEBUG

Marty Kuhrt's #include fixes for VMS

include stdarg.h since we use va_* stuff

added the sharing of DNS cache

removed the local variables for emacs and vim, use the new sample.emacs
way for emacs, and vim users should provide a similar non-polluting style

copyright year update in the source header

Updated more and now looks and and the API possibly works almost like the
design document specifies. There is still no code inside that uses this.

updated to use the modified share-types

updated source code boilerplate/header

Sterling Hughes brings the share interface