Optimtool

Improved Detail:
- remove input parameter named *res* of both methods of nonmonotonic_search which exists in v2.8.1, and reduce the computed times of *res.subs* operation, replace *res0* with a negative value of variable *d* (present as *dk* in barzilar_borwein method).

Simplified Details:
- disable .jacobian operation of any method of _search file, and input the first derivative from the main algorithms, mainly to reduce the gradient computed times of linear_search and nonmonotonic_search, in order to accelerate the execution of any method of constrain folder by reducing the computational burden of its search kernel.

Improved Details:
- reduced opening memory of hessiani in dfp method, v2.7.3 is an optimized version of newton_quasi compared to previous versions.
- reduce the calculation times of Lasso.approximate_point method, mainly to simplify the executed updated gradient in iterating points.
- unify the updated operation of penalty methods, and adjust the default epsilon of example.Lasso.* to balance precision in case of tests.
- select "L1" mode in obtaining the last iteration value of objective function in Lasso method before it was appended into the final output.

Upgraded Details:
- reduce the calculation times of bfgs and dfp method of newton_quasi file, mainly to reduce the updated runtime of Hessian matrix.

Enhancement:
- add MulType, PowerType, AddType to support the most common operators in constructing input conform to FuncArray.

> Users should make sure the differentiable objective function with local minima that can be constructed with operators from sympy and adapt to rules according to FuncType.

Improved Comparison:
- Enhance the comparison of internal values by taking indexes, like alpha_down from *barzilar_borwein*, pk from *levenberg_marquardt*, pk from *steihaug_CG*.