CHASE 0.7.1

pip install "chase-cps==0.7.1" (or chase-cps[rtl,z3]).

The diagrams after a review of every demo, and ports of two integer ranges.

Added:

• A variable shared as integers of two ranges (a port of 0..100 feeding one
  of 0..9) is one integer of the union of the ranges. In each contract its
  own range becomes a term: an assumption where it is an input, a guarantee
  where it is an output. The checks then say whether the values fit (a
  counterexample, the term of the range it breaks), and the wire is not
  red. Other types that differ are still an error.

Changed:

• The panel and the waveform float over the diagram, of frosted glass: the
  diagram goes on under them.
• One corner for every box: tags, contracts, the toolbar, the panel, the
  waveform.
• The hole of a quotient is pale yellow, so that it shows when the diagram
  is small.
• A C function with no clause has the contract (⊤, ⊤): its tag is M ⊨ C,
  not safe. The check is the same (no overflow, division by zero, or
  access out of bounds).
• The values of a step are written on the ports over the wires, and the
  same value at the two ends of a short wire once.
• The counterexample table scrolls by whole columns, its end too; long
  lines of code wrap in the panel.
• A quotient by a composition names its parts (Pipeline / (Producer ⊗ Consumer)); a range of one value is written {0}.
• Export: the SVG has the style of each element written on it, so other
  programs (Inkscape, Illustrator, slides) draw it as the page does, with
  its symbols; it has no background. The PNG and the PDF are on white, and
  the PDF is one page the size of the diagram.

Fixed:

• The PDF of a diagram was blank (the rules of the page for printing hid
  it).
• The wires from environments to what they drive could be drawn far above
  the boxes (Deadline): the wires of the top level are placed with their
  row.