Refactor: extend Feature with access attribute

Taking this a step further - would it make sense to extend the Feature class to support an “access” attribute similar to the bitness attribute that we previously supported (https://github.com/mandiant/capa/commit/55a5d10859e0a0e0d046c621bb4985faf9769e20).

where the “access” attribute is a simple enum e.g.:

class Access(Enum):
    Read = 1
    Write = 2

This would enable us to (optionally) extend the read/write specifier to all current features, including Property, and future features. This may even help reduce FPs e.g. the difference between cmp and mov using a number feature to detect PE parsing (we’d likely expect the number 0x5A4D to be read, not written, in this case) e.g.

- number/read: 0x5A4D

We currently use mnemonic features to accomplish the above example but that doesn’t easily allow for technology-agnostic rules e.g. a rule author wants to detect when the number 0x5A4D is read by both native PE and .NET executables.

_Originally posted by @mike-hunhoff in https://github.com/mandiant/capa/pull/1122#discussion_r943722740_

[mr-tz]

I’m leaning towards a separate branch/PR based on #1122 which is fairly big already. Maybe we branch off #1122 and merge in the Feature extension first?

[mike-hunhoff]

added in #1168