feat(admin): Improve commands + add spawn and learnspell

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 91.36691% with 12 lines in your changes are missing coverage. Please review.

Project coverage is 96.37%. Comparing base (f0e6ede) to head (ea8318b). Report is 2 commits behind head on master.

Files	Patch %	Lines
.../quatrevieux/araknemu/game/admin/player/Spawn.java	84.21%	10 Missing and 2 partials :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #339 +/- ## ============================================ - Coverage 96.38% 96.37% -0.02% - Complexity 9111 9142 +31 ============================================ Files 1405 1407 +2 Lines 23289 23419 +130 Branches 1484 1501 +17 ============================================ + Hits 22448 22570 +122 - Misses 634 640 +6 - Partials 207 209 +2 ```

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