More work on explicit sizes - the end is near!
Now redomap also internalises.
Fix size annotations for filter and map.
Make copy-propagator a little size-aware.
Make type-checker aware of size annotations.
Add some more type annotations when printing.
Permit size annotations to refer to same pattern.
Size-annotation related fixes to enabling optimisations.
Size annotation-related fixes to free variable searching.
Fix 99bottles test program to not abuse reduce.
Do not generate pointless shape-if-expressions.
Fix split/concat size annotations.