Initial rewrite.
Removed compiled py files, modified __init__.
Various changes.
Various changes and addition of Introduction library.
Addition of SaturatingSymbols
Minor changes
Minor changes, added `normalising symbols`.
Factories now produce identity operands.
Sensible default for SaturatingSymbol.
Minor changes to notebook.
Minor changes to notebook.
Modified to match PEP8 and PEP328
Added more thorough documentation. TODO: Complete.
Merged in abstractify, modified README