#3: LESS MIXINS: even a more general fibo maker

The selector can also be defined. Also multiple properties can be defined as well.

Signed-off-by: Amin Meyghani <amin.meyghani@quovo.com>
#3: fibo mixins and the docs

Add the fibonacci sequence related mixins and the documentatinos.

Signed-off-by: Amin Meyghani <amin.meyghani@quovo.com>