SPARQL Graph management and W3C results formatters

This release introduces the following features:

• Added complete support for SPARQL Graph management with ADD and DROP queries.
• Added formatters for formatting SPARQL results to W3C XML, W3C JSON, W3C CSV and W3C TSV.

What's Changed

• Bump codecov from 3.6.5 to 3.7.1 by @dependabot in #51
• Bump lodash from 4.17.15 to 4.17.19 by @dependabot in #50
• Bump jquery from 3.4.1 to 3.5.0 by @dependabot in #49
• Bump node-fetch from 2.6.0 to 2.6.1 by @dependabot in #52
• Modernize TypeScript code by @Callidon in #53
• Add support for formatting JSON by @Callidon in #55
• Add support for formatting query results to CSV and TSV by @Callidon in #56
• Add support for CREATE and DROP queries by @Callidon in #54

Full Changelog: v0.7.6...v0.8.0