4664: Update translations r=heinrich5991 a=def-
<!-- What is the motivation for the changes of this pull request -->
## Checklist
- [ ] Tested the change ingame
- [ ] Provided screenshots if it is a visual change
- [ ] Tested in combination with possibly related configuration options
- [ ] Written a unit test if it works standalone, system.c especially
- [ ] Considered possible null pointers and out of bounds array indexing
- [ ] Changed no physics that affect existing maps
- [ ] Tested the change with [ASan+UBSan or valgrind's memcheck](https://github.com/ddnet/ddnet/#using-addresssanitizer--undefinedbehavioursanitizer-or-valgrinds-memcheck) (optional)
Co-authored-by: def <dennis@felsin9.de>
-Lines 563, 944, 1175, 1178 & 1181: Removed tildes from "Volumen" (thanks to Lagar85).
-Line 1091: "APM" meaning is "Asesinatos Por Minuto" (Frags Per Minute)
-More little grammar/syntax changes.
Update spanish.txt
Added some tildes and removed 1 extra space.
Fixed syntax, so some sentences now have more sense.
Added some abbreviations to fit better in the UI.
Added Ryozuki's suggestions.
Please tell if you see something wrong :D
Seems to work on first try, I'm somewhat surprised :D
Future ideas (not for this change):
- I haven't checked how the performance impact is of a new skin joining,
might want to move the loading to a separate thread?
- Use the skins from download directory instead of redownloading? Might
want to compare modified time.
- Make all skins load on demand only to save some memory?