Simplex Solver

Modify simplex solver
modification of matrix
README test
readme
Update README.md
Merge pull request #12 from GuoSongtao/master

package LeastSquares
A huge update on array design

As detail array can a referred object right now. It is more convenient
to consider every row or column as a vector.
Merge remote-tracking branch 'origin/master'
Merge pull request #13 from GuoSongtao/master

little change in LS and python extension
delete damand file
code review of LeastSquares
overwritten
makefile overwritten
error
modification
makefile.in
add sparse matrix class and test
sparse matrix linear operations

Linear operations for sparse matrix is implemented like multiplication
and summation, subtraction etc.
delete cblas_example
umfpack is installed and is tested