Various fixes to `info.json` files, improved consistency

[Jackenmen]

List of changes:

• make required_cogs key a dict (change was required in League, Leveler, anarchy and oBoobs)

  It's nothing very important since nothing even uses this key, but required_cogs key should be a dict mapping a cogname to repo URL, e.g.

   {
       "required_cogs": {
           "adventure": "https://github.com/aikaterna/gobcog/"
       }
   }

  See docs for more info

• bot_version key is actually called min_bot_version and it should be a string (change was required in League, Leveler, account, anarchy and oBoobs)

  See docs for more info

• author key has to be a string (change was required in oBoobs)
• the way you wrote your name in author keys weren't consistent so I figured it might be good to just make it "Malarne (Malarne#1418)" in all info.json files (change was required in all cogs and repo's info.json)
• all keys in info.json file must be lowercase (change was required in account)

[Malarne]

Thanks :D