Update README to explicitly state its distinction

Full Changelog: 1.34.0...1.35.0

• Update README to explicitly state that this extension is a distinct fork of the original Git Graph.
• Clarify distinguishing features and additional value provided by this fork.
• Update branding and description to differentiate from the original extension.

New Tags Dropdown UI and other fixes

What's Changed

• A new dropdown menu has been added to filter the graph by tags
• Added double newline support by @KiljanK in #6
• add version number in package.json and .nvmrc by @natsuki-engr in #5
• select all text in field when widget called by @natsuki-engr in #4

New Contributors

• @KiljanK made their first contribution in #6
• @natsuki-engr made their first contribution in #5

Full Changelog: 1.33.0...1.34.0