Refactor to Simple HashMap. Docs. New Interface

[metaskills]

This work does a lot of work but is primarily meant to address #7 by providing a base simple HashMap interface rather than the old format which leveraged an internal HTTP server interface for the Runtime. Here are a few other things this pull request does:

• Lots of documentation. Call outs for missing sections.
• Clean up crates. Update new AWS SDK. Removed runtime. Use crate for lambda extension.
• Prepare for work needed in Binary & Library Data Sharing #4 to share parameter -> env hash.