Removed unused bullet
unnecessary absolute path for testdata

Hey,

I think the path to `understand/testdata` doesn't have to be absolute from the root of the filesystem. `./testdata` works quite well.
add star
cosmetic
simplify some type names
grammar doc updates
Merge pull request #3 from grant/master

Removed unused bullet
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shifting towards simpler grammar
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tuneups
star passes test
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f/r parsing
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