correct typo
separate htdp package into htdp-lib htdp-doc and an htdp package
that just pulls those two in: just the git mv commit
adjust info.rkt files for new htdp-doc pkg
fix contract
add image interop section to 2htdp/image
Fix dependencies.
Fix file tests to run without drracket.
Progress on fixing `pkg` tests.

 - They now compile.
 - The db tests now pass.
Run more tests in Travis.