from_range_uint added.
MatrixUInt added.
Exchange of rows based on selection of maximum absolute value in the column added. [pivot selection]
Some functions renamed.
we handle the case of 0 pivots.
fixed initialization problems in from_iter and diag_from_vec
more tests of gauss elimination.
renamed from_slice  to from_slice_cw. added some functions is_lt(), is_ut(), is_triangular()
from_iter renamed as from_iter_cw
renamed special to constructors
renamed from_range to from_range_cw, introduced a function from_slice_rw
renamed matrix_* functions to matrix_cw_* functions.
added some row wise constructor functions.
separate functions for extracting diagonal matrix and vector, functions for extracting lower and upper triangular matrices.
added some more unit tests
Introduction of MatrixType trait. Both Matrix and MatrixView implement this trait.
Matrix Introspection traits.