Rewrote squeeze to avoid commons-lang dependency

[DavyLandman]

I noticed we still had a commons-lang dependency. I thought we got rid of that 10y back when most of their string functions weren't safe for unicode.

There was on function still using it, so I rewrote that in regular rascal. I see no reasson to keep this in Java, unless it becomes a bottleneck.

And I added tests for it (that I first tested on the original code).