Nothing says holidays like the release of 0.7.0 and 0.7.1 🎁

• jonathandturner released 0.7.0, and then fixed the list of stable plugins and released 0.7.1 (#1100)
• andrasio added support for outputting the Line primitive with $it (#1085)
• andrasio also continued internal refactoring (#1080, #1081)
• sebastian-xyz did a lot of work to bring the books to the main Nu website (#1082)