Change the AST tests to what I expect.
Remove seg_statementlists from the AST.
Remove statementlists from the grammar.
Nuke statementlists from the AST printer.
Use blocks instead of statementlists in the lexer.
Use the forward declaration!
Deal with a few remaining bugs.
Merge pull request #14 from smashwilson/smash-blocks

Collapse seg_block_node and seg_statementlist_node.