Add options.strict to ignore individual url parsing errors

[Left47]

HAQ throws an error and halts when it encounters an invalid url. This is problematic when using email apis that use template placeholders, since one invalid url can prevent the whole template from being processed.

Example: <a href='%unsubscribe_url%'>Unsubscribe</a>

Added strict:false as an option to catch/ignore parsing errors at the url level, and leave invalid urls untouched while processing the rest of the file.

[zoellner]

Thank you for the PR. I would suggest to wrap only the new URL() statement in the try/catch block and also check for err.code ERR_INVALID_URL instead of treating all errors the same way