Add exercises for the "Queries" Exam Objective (v6.5)

[glenacota]

Topics:

• Write and execute a search query for terms and/or phrases in one or more fields of an index
• Write and execute a search query that is a Boolean combination of multiple queries and filters
• Highlight the search terms in the response of a query
• Sort the results of a query by a given set of requirements
• Implement pagination of the results of a search query
• Use the scroll API to retrieve large numbers of results
• Apply fuzzy matching to a query
• Define and use a search template
• Write and execute a query that searches across multiple clusters