Add session options to allow drill working with non standard json strings number literals like: NaN, Infinity, -Infinity. By default these options will be switched off, the user will be able to toggle them during working session.
1. Added two session options store.json.reader.allow_nan_inf and store.json.writer.allow_nan_inf that allow to read/write NaN and Infinity as numbers. By default these options are set to true.
2. Extended signature of convert_toJSON and convert_fromJSON functions by adding second optional parameter that enables read/write NaN and Infinity.
3. Added unit tests, including tests for math functions.