Let us use lower cases for the names of algorithms within the code

[zaikunzhang]

https://github.com/blockwise-direct-search/bds/blob/85ad91015f809cb69a354e3555a382ed2860f94e/src/bds.m#L226

Within the code of BDS, let us use lower cases for the names of algorithms (CBDS, SBDS, RBDS, PBDS, ...).

When you need to identify the algorithm using the name, do the following.

1. strcmpi(Algorithm, "cbds") checks whether Algorithm is "cbds", case-insensitively.
2. If you use a switch, do the following.

   switch lower(Algorithm)
   case {"cbds"}
   ...
   case {"sbds"}
   ...
   end

[Lht97]

I have changed the names of algorithms in bds.m to lower cases and I allow users to input upper cases.