[Printing-architecture] libcups v3.0b1

All,

libcups v3.0b1 is the first beta release of the CUPS v3 library and tools which remove deprecated APIs, add new APIs, and normalize existing APIs.

	https://github.com/OpenPrinting/libcups/releases/v3.0b1

Changes include:

- Documentation updates (Issue #32)
- Split out libcups and tools from CUPS 2.x.
- Simplified the configure script.
- Now require a C99-capable C compiler.
- Now require GNU TLS, LibreSSL, or OpenSSL.
- Now require ZLIB.
- Now require POSIX or Windows threading support.
- Now require the `poll` function (`WSAPoll` on Windows).
- Now install with a prefix by default to allow coexistance with CUPS 2.x (Issue #21)
- Added new `GENERATE-FILE` directive for `ipptool` test files.
- Added new `ATTR-IF-DEFINED` and `ATTR-IF-NOT-DEFINED` directives to IPP data files (Issue #3)
- Added `ippFile` API for working with IPP data files as used by `ipptool`, `ippexeprinter`, and other tools (Issue #14)
- Added a roll to the default color ippeveprinter printer.
- Added new DNS-SD API (Issue #19)
- Added new PWG media sizes.
- Added new `WITH-ALL-VALUES-FROM` predicate for ipptool files (Issue #20)
- Added new `SAVE-ALL-CONTENT`, `WITH-ALL-CONTENT`, and `WITH-ALL-MIME-TYPES` predicates for ipptool files (Issue #22)
- Added, modernized, and promoted the localization interfaces to public API (Issue #24)
- Added public JSON API (Issue #31)
- Added new `basename` variable for use in ipptool files (Issue #44)
- Updated the CUPS API for consistency.
- Fixed ipptool's handling of EXPECT for member attributes (Issue #4)
- Fixed ipptool's support for octetString values (Issue #23)
- Removed all obsolete/deprecated CUPS 2.x APIs.
- Removed (obsolete) Kerberos support.
- Removed support for SecureTransport (macOS) due to deprecation of the platform API.
- Removed support for SChannel (Windows) due to restrictions on its use in
  domain accounts.

Enjoy!

________________________
Michael Sweet