DEVELOPMENT.md: restore default PTS instance

This simplifies interactive use. We might want to pick a different
default, but I'm not sure what, so I just restored using
fomegastar (which was the previous default).
DEVELOPMENT.md: correct how to show types

Since types are now values, we need reification to print them back.
DEVELOPMENT.md: simplify how to show types
DEVELOPMENT.md: other corrections/updates
Interactive.hs: make getBindings useful again

Now the code in DEVELOPMENT.md will work again.
DEVELOPMENT.md: discuss showing module contents
Merge pull request #126 from Blaisorblade/topic/development-md-update

Update DEVELOPMENT.md