Adopt a documentation style guide

[yamgent]

We have adopted standards for our coding style, but we do not have a guide for our documentation style.

We can consider adopting a documentation style guide for our open source projects such that the readers of our documentation (both users and developers) have an easier time reading them.

We can either write our own by taking the concepts from CS2101, such as passive voice, second person, conciseness and consistencies. Alternatively we can also adopt wholesale the guides from other open source projects, such as Google's one: https://developers.google.com/style/. The one by Google seems to be pretty useful as it also delves into the concepts that I have mentioned earlier.

[damithc]

Good idea @yamgent
Google guide looks good.
Do a PR to add it when you have time.