fixed java.lang.NumberFormatException ...

when using decimal values with locales having a decimal separator other than "."

https://groups.google.com/forum/#!msg/dbfit/2JNsutqfVV4/8Br6jx9Eh7cJ

My tests are working now, but "gradle clean fastbuild" throws java.lang.AssertionError: wrong expected:<0> but was:<4> in test classMethod.

It'll certainly break things for people who rely on the number format to use a period as decimal separator. I was trying to find out how date/timestamp related tests deal with different locales, but didn't find any. Perhaps we'll need an option to specify the locale per page.

Is it safe to use NumberFotmat.getInstance? Some time ago I've done a simple experiment with BigDecimal parsing where I used the following:
``` java
    public Number parseNumber(String s) throws Exception {
        DecimalFormat nf = new DecimalFormat();
        nf.setParseBigDecimal(true);
        return nf.parse(s);
    }
```

I.e. - explicitly set BigDecimal as return type since by default it's not [as per the docs](http://docs.oracle.com/javase/7/docs/api/java/text/DecimalFormat.html#isParseBigDecimal()).