fix BigDecimal bug with negative integer exponents
fix BigDecimal bug with negative integer exponents

non/spire,guersam/spire,adampingel/spire,woparry/spire,siddhartha-gadgil/spire,codeaudit/spire,kevinmeredith/spire,woparry/spire,kevinmeredith/spire,JackSullivan/spire,AlecZorab/spire,siddhartha-gadgil/spire,AlecZorab/spire,guersam/spire,codeaudit/spire,rklaehn/spire,JackSullivan/spire,tixxit/spire,rklaehn/spire,non/spire,adampingel/spire,tixxit/spire