Fix and tests for issue #37

Bug: When an IN/NOT IN predicate is not the first to be added, the
statements.js:buildOperator function includes the whole outValues array
as values.

How to reproduce:
See the tests added. These will fail before this fix.

Fix:
The utils.js:quote function now takes the value being added as third
parameter. When quoting an IN/NOT IN operator, the valuePos array
starts at the correct index (outValues.length - value.length + 1).