fix 400 errors from /api/preview

Dynamic categories

Undid storing categories in strings.js, instead using the localization method in songselect.js. category info gets passed down to view.js.

Moved categories to its own object instead of allstrings and adjusted code in the other files in order to maintain multilangual support

Bug fixes

- Fixed touch multiplayer drum being too small and nameplate drawing on top of it
- Fixed #lyric lines being forced to be lowercase and appearing too early
- Fixed exiting session while someone else is using netplay sending you to difficulty selection of the song that the netplay person has selected
- Fixed ≠MM title on song select not having the first symbol rotated
- Fixed nameplate cache in song select and in game not getting cleared
- Increased ping timeout for multiplayer

Admin page fixes
- Add meta viewport tag so that the admin pages can be opened on mobile
- On song list, songs that are not enabled are now marked
- Disable tabbing through diverge notes checkboxes in courses when adding or editing a song
- Add Hash to song adding
- Display an error if a local chart file has not been found while calculating hash
- If calculating the hash results in an error, do not discard all other changes