Getting Started Guide

[jontlo]

Description

Adds documentation to update pip to the current version in "Installing" section. Edits documentation for how to navigate to Environment Variables in Windows 11 in "Installing on Windows" section. Adds documentation for how to run beets package if scripts are not in PATH in "Installing on Windows" section.

To Do

• [ x ] Documentation. (If you've add a new command-line flag, for example, find the appropriate page under docs/ to describe it.)
• [ x ] Changelog. (Add an entry to docs/changelog.rst near the top of the document.)
• [ ] Tests. (Encouraged but not strictly required.)

[JOJ0]

@jontlo what do you think of our suggestions? Questions? Don't like them? Thanks for any response :-)

[JOJ0]

@jontlo? only tiny fixes away of a merge!