Ajv doesn't work

[yorinasub17]

The current approach using Ajv doesn't work because the required import paths are not supported in senc. Specifically, the following issues currently exist:

• If the import is a path to a js file in the node_modules dir, then it doesn't have the extension. We need to check both PATH.js and PATH/package.json (currently only check the latter). Add support for importing files in node_module directly senc#17
• Ajv is all commonjs, so we need to add in support for handling commonjs in the deno runtime (deno doesn't support cjs natively). Allow runtime to handle CJS senc#7