Add IPS .p5m manifest parser

[andrew]

Parse dependency information from IPS package manifests (.p5m files) used by OpenIndiana, OmniOS, and Helios.

• Backslash line continuation for multi-line depend statements
• require-any emits one dependency per fmri alternative
• Skips macro references ($()) and __TBD placeholders
• FMRI parsing strips pkg:/ prefix, publisher, and build metadata after comma
• Scope mapping: require/require-any/group/incorporate to runtime, optional/conditional to optional

[Toasterson]

Quick note on macros and split lines. If you see such manifests they are incomplete and will go through pipeline programs namely pkgmogrify and pkgdepend the second one resolves elf library dependencies. The final manifests can be fetched from the REST server only in most cases and are also present in the JSON catalog file catalog.dependency.C which has the simplest representation of manifest dependency lines.