SMTLIBQueryPrinter emits too many spaces when not in human readable mode

[delcypher]

SMTLIBQueryPrinter emits too many spaces when not in human readable mode. The problem is that the class conflates separators with new lines. Several tests depend on this behaviour which is going to cause problems. It is also not very efficient to emit spaces for no good reason.

We should fix the design and then fix those tests.