[Typo3-documentation] General rules for TYPO3 docs

[Jean-Marie Schweizer]

> As far as I know, these are specific commands for a specific editor? If 
> so, I think they should be removed. Maybe if the text said somethink 
> like "This is how you do it in XXX editor on Linux" it could be ok...
> 
> What do you think?

I can do that.

> === About images
> In general I think images should not contain any part of the web browser 
> window. Normally you should cut your screenshots so that just the 
> _page_content_ is seen. In this way we both keep the documents slightly 
> smaller and get a document that is web browser / operating system neutral.
> 
> What do you think?

Makes it more complicated but I can do that too.

Jean-Marie