Curl on Windows

[Brad Anderson]

The newly accepted curl library sadly didn't get included in the 
2.058 release as it wasn't added to the Windows makefile.

I created a pull request to resolve this [1] but it had to be 
reverted because it broke the auto tester.

The tester broke because of the missing curl.lib library.  I've 
suggested curl.lib be included with phobos but Brad says it can't 
due to licensing problems.  I couldn't find a discussion on the 
newsgroup about what problems there are.

Curl is licensed under MIT [2]. The optional SSL support for curl 
uses OpenSSL which is dual licensed under both Apache License 1.0 
and SSLeay License, a 4-clause BSD License derivative [3].

I'm no expert on licensing issues but the only issues I can see 
are, first, the copyright notice of the Curl and OpenSSL licenses 
must be displayed whether it is distributed in binary or source 
code form (easily added as a text file and, for good measure, in 
a licensing page in the installer).  And second, the advertising 
clauses in OpenSSL:

      * 3. All advertising materials mentioning features or use of 
this
      *    software must display the following acknowledgment:
      *    "This product includes software developed by the 
OpenSSL Project
      *    for use in the OpenSSL Toolkit. 
(http://www.openssl.org/)"


and

      * 3. All advertising materials mentioning features or use of 
this software
      *    must display the following acknowledgement:
      *    "This product includes cryptographic software written by
      *     Eric Young (eay at cryptsoft.com)"
      *    The word 'cryptographic' can be left out if the rouines 
from the library
      *    being used are not cryptographic related :-).
      * 4. If you include any Windows specific code (or a 
derivative thereof) from
      *    the apps directory (application code) you must include 
an acknowledgement:
      *    "This product includes software written by Tim Hudson 
(tjh at cryptsoft.com)"

Both of these sound fairly reasonable to meet.  Lots of other 
software does (Python from Windows, Google Chrome, etc.)

Is there anything I'm missing here?

If not, we can talk about how to approach including it in the 
release.

[1] https://github.com/D-Programming-Language/phobos/pull/458
[2] http://curl.haxx.se/docs/copyright.html
[3] http://www.openssl.org/source/license.html