ISSUE-31 - Implement Standardized type-safe SeleniumErrors

[AdonisCodes]

Reason

The Library currently doesn't support an easy way to recognize what type of exceptions are being thrown. This PR implements a similar concept to how alamofire adds an extension onto the generic error object to try and identify what type of error it is. This PR also touches all the tests that are looking for a specific exception type.

Tech Details List

• Implements isSeleniumError(ofType: SeleniumErrorType) -> Bool that validates if an error is a specific type
• Implements asSeleniumError(ofType: SeleniumErrorType) -> SeleniumError? that returns a SeleniumError if the condition is met
• Implements a public enum SeleniumErrorType mapping error values
• Enhances all tests that checks for SeleniumError to also validate the error type that was thrown

Tasks:

• Document testing Instructions
• Refactor tests to check error type as well

Links:

ISSUE-31
resolves #31

Testing

• Ensure unit tests pass

[vimscientist69]

The tasks above, are they completed? Are they important for this pull request?

[vimscientist69]

Looks good overall. Make a commit to fix return false blocks to be on separate lines.