Support markdown tables

Problem

Right now, markdown tables are just rendered as plain text, like this image

They should be rendered as an actual table, like this:

| Month | Savings |
| -------- | ------- |
| January | $250 |
| February | $80 |
| March | $420 |

They should also support alignment using ----:, :----, and :----: like this:

| Month | Savings |
| -------- | -------: |
| January | $250 |
| February | $80 |
| March | $420 |

Discord does not support markdown tables, but it seems reasonable for Fluxer to support them.