
Analitza:
- Partial derivatives
- Simplification for x^3*3/x-> 3*x^2
- Simplification for sum
- Change QList<Object*> for a typedef

Expression:
- Copy on write for m_tree

2D:
- Shared functions Console <-> 2D
- Delete 2D functions
- Sort 2D functions
- Moving on small viewport step is too large.
- Review keyBindings for zooming out.

Doc:
- Document about piecewise
