Revisit the formatting and the PICTURE syntax.

either fully support the cobol picture syntax as described [here](http://www-personal.ksu.edu/~mchaney/mn670/cobol4.htm) and [there](http://www.pgrocer.net/Cis12/cobol3.html), or maybe map to a dotnet friendly alternative like implementing the [IFormatProvider](https://msdn.microsoft.com/en-us/library/system.iformatprovider%28v=vs.110%29.aspx) and [ICustomFormatter](https://msdn.microsoft.com/en-us/library/system.icustomformatter%28v=vs.110%29.aspx) interfaces and using `string.Format`.

Start by reviewing the COBOL PICTURE syntax in the two linked references and comparing it with .NET's IFormatProvider and ICustomFormatter interfaces. Clarify whether the goal is full syntax support or a .NET formatting alternative; done should mean the selected approach and supported scope are explicitly defined and validated against representative PICTURE formats.

Written by the indexing model from the issue text.