Migrate contents to new website

This mainly involves converting Jekyll templates to Hugo shortcodes, ensuring the layout remains reasonably consistent, and add more styling when needed. More detailed instructions will follow.

- Guide
- [x] #11
- [x] #12
- [x] #13
- [x] #14
- [x] #15
- [x] #16
- [x] #10
- [x] #17
- [x] #18
- Tutorial (the classic Tour of Heroes)
- [x] #19
- [x] #20
- [x] #21
- [x] #22
- [x] #23
- [x] #24
- [x] #25
- Advanced
- [x] #26
- [x] #27
- [x] #28
- [x] #29
- [x] #30
- [x] #31
- [x] #32
- [ ] #33
- [x] #34
- [x] #35
- [ ] #36
- Other
- [ ] #37
- [ ] #38
- [ ] #39
- [ ] #40
- [ ] #41
- [ ] #42
- [ ] #43