Text corrections

[dragonito]

Some text corrections

[javiereguiluz]

Robin, thanks for this improvements.

Please note that while merging I reverted the change that added a , after e.g. You are technically right (as explained in https://jakubmarian.com/comma-after-i-e-and-e-g/), but we have lots of e.g. examples in the docs and we can't change all of them (please, nobody create a Pull Request for this because it won't be merged because of the great effort needed from contributors to do so across all branches). So, given that not adding a comma is OK for British English and for some of American English, let's keep it like that. Thanks for understanding.