Extract functional roles from question formulator output

[nsbgn]

As discussed in #1, the issues of constructing a question and of extracting functional roles should be separated. For this, we need to figure out how to replace or adapt the ANTLR parser for the recognition of functional roles.

Issue #5 discusses changing the output of blocks to simplify this step. The issue you're reading now is about taking that output and actually producing the functional roles/transformations.

Ideally, the information needed to both show question blocks and extract functional roles from their output would be declared in a single grammar file. This is ideal because it would mean that phrases and their functional roles are kept in a single place; and that the procedural code to generate the blocks and transformation extraction can be kept separate from the declarative code for the grammar. This would allow those who edit the grammar to focus on the important bits. It may or may not be possible; I will need a better understanding of the blocks & parser.