Introduce mining to the game

[yehric2018]

Now that players can equip a weapon, we can finally create something for them to do in the world: mining! Players have something to mine with: a pickaxe, or any weapon (which would be less effective), but we don't have something to actually mine.

We will begin on introducing a new entity type, Minable, which represents something that can be mined. The idea is that if you run the !attack command on a Minable, you have a chance of acquiring different types of resources based on the composition of the Minable. Such resources are as follows:

• Stone
• Coal
• Iron
• Silver
• Gold
• Diamond
• Platinum

Each individual Minable will be filled a certain percentage of each of these. When attacked, you have a chance to get a certain number of these resources based on the pickaxe quality and your player's strength stat. So over time as a Minable is continuously mined, it will eventually run out of resources completely. These resources will automatically be dropped in the miner's inventory upon collection, which can later be used to craft/smith items (which we can implement later).

Steps to complete:

• [x] Create new static items for each of the mined resources (these items don't do anything on their own, but can be used to craft other items later)
• [x] Make sure Entity.id starts from 2000 from auto-generated for now on so we can enter initial entities into our world (hint: take a look at https://stackoverflow.com/questions/10494033/setting-sqlalchemy-autoincrement-start-value)
• [x] Create a Minable model that inherits from Entity and consists of composition fields
• [x] Create the attack command to only respond to Minables: Produce resources by random, place them in your inventory, and remove those resources from the Minable. This should take into consideration whether you have a pickaxe or not.
• [x] Create !attack tests specific for mining in its own file, make sure to test thoroughly while mocking the random.randint function
• [x] Create an initialization script that consists of all the base game entities that we want to produce. Populate the mines with some Minables.
• [ ] Create a basic !here command. For now, it will only consist of the interactable entities in the zone (like minables) and players in the author's current zone
• [ ] Generate tests for the !here command.
• [ ] Finally, add both !attack and !here to the main bot and see if mining works properly!

[yehric2018]

Update: The mining functionality now works successfully in the dev server, and allows us to mine resources from a Minable. The !here command is all there is needed to implement, however we will wait a bit to implement this. Therefore, I will close this issue as completed and move the !here functionality to a different issue, since it is quite separate.