Parse more metadata from the SERP URL

[janheinrichmerker]

In this issue, I'd like to collect all types of metadata that can be found in a SERP URL, and keep track of what is supported in the AQL implementation.

• query
• page
• offset
• user identifier (Parse user identifiers from URL #90)
• language (Parse language from URL #91)
• geolocation (Parse regional information from URL #92)

If you'd like to propose a new field, just comment below, and ideally also post an example.