Test POST methods for objects that contain references

[ruists]

Test the POST methods for BaseWeapon, BaseSummon, Weapon, Summon and Character to see if they work as intended after adding/modifying validations.

[ruists]

Also test BaseCharacter, since its methods fit the criteria mentioned above (contains references to other MongoDB collections).
Most of the validations that were done in Character are now done in BaseCharacter too, but Character still needs to be tested.

[ruists]

POST methods for Base collections were tested successfully.
User-dependent POST methods still need to be tested further.