New library packages

1. bianchi (3-d Lie algebra classification package).
2. cartan (special-purpose relativity tensor package using Cartan's formalism).
3. debever (special-purpose relativity tensor package using Debever's formalism).
4. finance (amortization and Black Scholes stock call option pricing).
5. geom3d (3-d geometry package).
6. heap (priority queue data structure).
7. liesymm: (Lie symmetries package - obtains the determining equations for the Lie symmetries of a system of partial differential equations).
8. logic (boolean algebra package).
9. oframe (orthonormal frame package using the Ellis-MacCallum formalism).
10. petrov (Weyl tensor classification package).
11. plots (2-d and 3-d special plots package)
12. tensor (relativity tensor package).