docs: Update versions and feature flags

[crandmck]

Changes in this pull request

Update crate version in docs. Update feature flag docs.

Per @mauricefisher64:

• Removed doc for these feature flags: openssl and openssl_sign
• Added description of pdf

Checklist

• This PR represents a single feature, fix, or change.
• All applicable changes have been documented.
• Any TO DO items (or similar) have been entered as GitHub issues and the link to that issue has been included in a comment.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 78.91%. Comparing base (1cda7bd) to head (36ea663).
Report is 1 commits behind head on main.

Additional details and impacted files

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  Coverage   78.91%   78.91%           
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  Files         147      147           
  Lines       34805    34805           
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  Hits        27466    27466           
  Misses       7339     7339           

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[mauricefisher64]

With the refactoring of our crypto code, openssll, and openssl_sign don't make much sense. The default behavior is always to use OpenSSL unless we do some wasm/wasi. These feature flags could be removed if someone goes through and cleans up the code. I think they are on in unit tests and samples at the moment. No real functionality is using these flags at the moment.
"pdf" feature enable PDF read support

[crandmck]

I removed the openssl and openssl_sign feature flags from the doc, since it sounds like they don't actually do anything even though they are technically supported.

Added short desc of pdf feature flag.

The default behavior is always to use OpenSSL unless we do some wasm/wasi.

This sounds like something that needs to be added to the docs. By default, is OpenSSL a prerequisite for using the Rust library? Then at a minimum, we need to say that, and ideally provide some instructions on what you need to do (download/install OpenSSL, and ... ?)

We do mention OpenSSL in Signing manifests, but if Rust lib now strictly required by default we should at least mention that.

What does "we do some wasm/wasi" mean? Should we explain what to do?

[mauricefisher64]

Why do we have to tell them the what crypto is used. If you build c2pa-rs it will use OpenSSL. If you build c2pa-rs for wasm/wasi it will use RustCrypto. There is currently nothing for users to do.