anchor/pymarquise — pull request #9 by barneydesmond (2014-08-04 05:31:28+00:00)
Title: Null values are allowed in a sourcedict

From discussion we determined that a null key is no good, but a null
value is okay. As we've specified that everything is strings, a null
value is coerced to zero-length string and then treated accordingly.

This PR is also open to allowing more null values, discussion is needed. Do we allow null values for an extended data point? Is the idea of a null value undefined for simple data points?