[Core] Added separate dev cog

This is enabled with the cli flag --dev

core/dev_commands.py

@@ -0,0 +1,65 @@
+from discord.ext import commands
+from core.utils.chat_formatting import box
+from core import checks
+import asyncio
+import discord
+
+
+class Dev:
+    """Various development focused utilities"""
+
+    @commands.command()
+    @checks.is_owner()
+    async def debug(self, ctx, *, code):
+        """Evaluates code"""
+        author = ctx.author
+        channel = ctx.channel
+
+        code = code.strip('` ')
+        result = None
+
+        global_vars = globals().copy()
+        global_vars['bot'] = ctx.bot
+        global_vars['ctx'] = ctx
+        global_vars['message'] = ctx.message
+        global_vars['author'] = ctx.author
+        global_vars['channel'] = ctx.channel
+        global_vars['guild'] = ctx.guild
+
+        try:
+            result = eval(code, global_vars, locals())
+        except Exception as e:
+            await ctx.send('```py\n{}: {}```'.format(type(e).__name__, str(e)),)
+            return
+
+        if asyncio.iscoroutine(result):
+            result = await result
+
+        result = str(result)
+
+        if ctx.guild is not None:
+            token = ctx.bot.http.token
+            r = "[EXPUNGED]"
+            result = result.replace(token, r)
+            result = result.replace(token.lower(), r)
+            result = result.replace(token.upper(), r)
+
+        await ctx.send(box(result, lang="py"))
+
+    @commands.command()
+    @checks.is_owner()
+    async def mock(self, ctx, user: discord.Member, *, command):
+        """Runs a command as if it was issued by a different user
+
+        The prefix must not be entered"""
+        # Since we have stateful objects now this might be pretty bad
+        # Sorry Danny
+        old_author = ctx.author
+        old_content = ctx.message.content
+        ctx.message.author = user
+        ctx.message.content = ctx.prefix + command
+
+        await ctx.bot.process_commands(ctx.message)
+
+        ctx.message.author = old_author
+        ctx.message.content = old_content