NEW (Extension) @W-16002080@ Add eslint support and additional parameters for the scan

[jag-j]

This PR does the following:

• Adding eslint support to the VS Code Extension. We do this by adding eslint-lwc as the default engine that would be executed. Users can change this to eslint or eslint-typescript in the settings.
• The list of engines to run is completely configurable and hence pmd can be removed if needed.
• Exposes a “normalize severity” flag as a setting and when that is turned on, we normalize the severity similar to CLI. This flag is turned off by default.
• Exposes a “category” flag as a setting that is empty by default and can be overridden to a value by the users. When set, only those category rules are scanned.