0.4.0

• The algorithms are now configured via structs, the traits are dropped.
• Provide ClassicalGramSchmidt, ModifiedGramSchmidt, and
  ReorthogonalizedGramSchmidt (known as cgs, mgs, and cgs2 in the
  literature, respectively);
• cgs and cgs2 are implemented using blas routines (major speedup!);
• All routines are now able to handle column-major (Fortran-) and row-major (C-) order
  of the input matrices;
• Remove parallel code.