172 improve documentation add readme files

[gangov]

No description provided.

[ueco-jb]

Apply first comment in all files.

• don't put filler stuff, why mentioning for example

**return type:**
`void`

(which is also invalid, because 1) there is no return type; 2) there is no void type)

• fix formatting, put plain text as plain text and code as code

[ueco-jb]

@gangov Please see the changes I introduced in the last commit and apply them to other readmes.

[ueco-jb]

LGTM

Great effort. Seems like a pain in the back, but you'll see that it will ease a lot of work in the future for new people.