Free Meter - increasing the barnumber wherever you want

If you do not want to use lilypond's automatic barlines but rather just insert barlines with \bar, the bar counter will not be increased, and therefore two problems may occur:
This snippet defines a function, \increaseBarNumber that - yeah - increases the barnumber, thereby making accidentals and typeset barnumbers behave correctly. Just call it whenever you insert a manual bar.
Also defines short hand functions \ibar and \nibar - as illustrated by the example.