Reorganized source structure
Relaxed build dependencies
Put an README.md under track
Revert "Recovered the original source structure"

This reverts commit 29117c95f03376a135a9c1db2a69a02bd58f6adb.
Sychronized source structure recovery
Merge branch 'master' of https://github.com/Toxaris/pts
Fix #25: ensure that cabal sdist produces a complete, compilable distribution
Merge branch 'master' of github.com:plmday/pts

Conflicts:
	README.md
Merge pull request #30 from Blaisorblade/master

Fix #25: ensure that cabal sdist produces a complete, compilable distribution
Add description to please 'cabal check' (see #29)
Add source-repository head (see #29).
Fix test case generation (see #23 #31).

The old code never generated lambda, Pi, or ifzero expressions,
because the second half of arbitraryTerm was parsed as:

  if size >= 2 then
    ...
  else
    ([] ++ if size >= 3 then ... else [])
Allow generating 'Nat' (see #31).

The old code never produced C 0 == nat.
Avoid generating unusual constants (see #31).
Implement tool to figure out name and version of the current package (for #26).
Merge branch 'master' of https://github.com/Toxaris/pts
Improved interfaces for PTS instances