Ruleminer

- Fix for abs-function where lower < 0 and upper > 0 (then the real lower bound is 0)
- Correction for logging of <=, <, >=, > comparisons

- Two bug fixes in corr-function

- Added <=, <, >=, >-operators that take tolerance into account
- Applied sqrt in the corr-function
- Added round, ceil and floor-functions
- Reformatted comparison-logs: {LHS - RHS = diff} operator [LHS_min - LHS - RHS_max + RHS, LHS_max - LHS - RHS_min + RHS]

- Added 'contains' and 'not contains' comparison operators

- Added intermediate results for unequalities
- Refactoring for logging intermediate results

- Added intermediate results for equalities and statistics