update API, update algorithm for matrix multiplication
update some example
update matrix multiply example, and update README
Update README.md
Update README.md
support generate random matrix in memory

modify Marlin project  structure.
Update README.md
modify API
add testsuite and support generating zeros matrix
refactor DenseVecMatrix and modify saveToFileSystem API
modify examples and data files
modify README
remove all content about `IndexRow`
update testSuite
support save/read SequenceFile
modify MTUtils

fix bug about loading matrix from files
improve performance when several matrices multiply
improve performance when several matrices multiply
update detail

fix a bug when a DenseVecmatrix multiply a BlockMatrix
support cBind

support cBind API and fix bug when matrices multiplication