General development process

- new cog commands
- new voice cog
- new requirements.txt
- adjusted readme
- added Dockerfile for faster deployment (still WIP)
- other general things

Dockerfile

@@ -0,0 +1,11 @@
+FROM python:3.6
+
+MAINTAINER Marco Thomas
+
+RUN mkdir /aquabot-docker
+WORKDIR /aquabot-docker
+COPY . /aquabot-docker
+
+RUN pip install --user -r requirements.txt
+
+CMD ["python", "aquabot.py"]