* [curl] Add support of different features.
Default-Features: openssl, http2, ssh (as in previous builds)
Feature: curl
Description: Builds curl executable (placed in the /tools directory)
Feature: http-only
Description: Disables all protocols except HTTP/HTTPS/HTTP2
Feature: http2
Build-Depends: nghttp2, openssl
Description: HTTP2 support (requires openssl)
Feature: openssl
Build-Depends: openssl
Description: SSL support via OpenSSL
Feature: winssl
Description: SSL support via Schannel
Feature: ssh
Build-Depends: libssh2
Description: SSH support via libssh2
* [cpr] Add features of the curl library.
* [cpr] Remove transitive features
* [curl] Remove http2 from default features. Remove winssl feature. Rename "curl" feature to "tool".
* [curl] Fixup curl -> tool renaming
* [curl] Further refactoring of WINSSL/Openssl -- use single ssl feature.
