Shake 0.13 released

Summary: Shake 0.13 is out, which contains a few API changes and several new features.

I've just released Shake 0.13. There are several new features, which I'll blog about in more detail over the next few weeks. If you're upgrading:

• ShakeOptions has additional fields, as it almost always does. Don't pattern match on this type directly, use record updates/selectors. The new member is shakeChange which lets you pick between basing file checking on modification time (the default), file digests, or combinations thereof.
• shakeReport is now [FilePath] instead of Maybe FilePath. You can now write multiple profiling reports, specify - to output a simplified report on stdout, or files ending with .json to generate JSON output.
• Shake is replacing **> with |*> , ?>> with &?> and *>> with &*> - although the old operators will be around for a few versions yet. The new operators are hopefully more memorable - they are either OR rules (||) which match build any one of several files, or AND rules (&&) which build multiple files simultaneously, on top of the standard *> and ?> rules.
• defaultRule is deprecated, and should be replaced with priority 0 . rule. The new priority mechanism allows defining rules at different priorities, which *> takes advantage of, so that now fully explicit matches take precedence over file-pattern matches.
• Development.Shake.Sys is gone and all system calls are now marked deprecated. Please use cmd or command instead.
• File times are recorded to higher precision, so files written in a fast loop are now likely to be detected as changing.
• The Ninja emulation now supports -t compdb, which is useful for CMake.

I don't expect these changes to hit many users, and all should be fairly localised tweaks.