Draft: Adapted input boxes to use Units->Decimals pref setting
Draft: Small bugfix in trimex
Unit.cpp/Unit.h: Added get...Dimension() function calls for missing elements of unit signature.
Added PropertyQuantity to the type system.
Initial commit for Spreadsheet module (C++ version).
Added PropertyQuantity to the type system.
Fixed spreadsheet import/export functions.
Fixed spreadsheet "open" command.
Added recompute() calls to spreadsheet commands.
Fixed isTouched() methods in Expression class hierarchy.
Implemented FunctionExpression::toString().