The %number macro does not interpret (precision, scale) consistent with ANSI SQL

[ghost]

Precision is the total number of the digits in a number. Scale is the number of digits to the right of the decimal point.

In dg-example-default, samplemachine.xml defines var_2_6 as expr="%number(5,2)". DG generates values such as 85829.40 and 61140.01. To be consistent with the ANSI definition, the generated values should be like 858.29 and 611.40

[mibrahim]

Tasks:

1. Update the docs at https://github.com/FINRAOS/DataGenerator/blob/master/docs/transformers/EquivalenceClass.rst
2. @leeny34 update the implementation of number to reflect the correct interpretation of precision / scale

References:
https://docs.oracle.com/javase/7/docs/api/java/math/BigDecimal.html
https://cwiki.apache.org/confluence/display/Hive/LanguageManual+Types#LanguageManualTypes-Decimals

[mibrahim]

Fixed by #272