Finish all the bstrlib unit tests.

Wrote small unit tests for functions blength, bchar and bformat.
Need to run valgrind on the unit test file to check for the copious amount
of memory leaks inside of the unit tests.
Remove white spaces in the darray files.

Use emacs delete-trailing-whitespace option before saving to delete
needless whitespaces
Add binary search, and insert in sorted order as darray operations

Binary search works as implemented in the LCTHW exercise.
Insert in sorted order naively adds the entry and then sorts the
Dynamic array after.