Handle multiple errors in response

[trvrnrth]

Goal

Include lists of errors as returned from some API endpoints (eg. configure an integration) in raised Bugsnag::Api::Error messages.

Design

Added secondary check for errors in order to maintain existing error message for possible compatibility reasons.

Changeset

• Added secondary check for errors
• Tidied up whitespace, unused variables and docs

Testing

Manually tested with:

Bugsnag::Api::Client.new
Bugsnag::Api.get("projects/test/configured_integrations")

which raises:

Bugsnag::Api::Unauthorized:
  GET https://api.bugsnag.com/projects/test/configured_integrations: 401 - Errors: ["Authentication Required"]

[trvrnrth]

Alternatives which break complete backwards compat for message parsing would be:

errors = Array(data[:errors] || data[:error])
"Errors: #{errors}" if errors.any?

or

errors = data[:errors] || (data[:error] ? [data[:error]] : nil)
"Errors: #{errors}" if errors.any?

[trvrnrth]

We may also want to pretty print lists of errors in some manner rather than relying on Array::to_s.