Created unit tests.

* Created unit tests for existing functions, with at least one test per
  template.
* Fixed bug in MinMaxATypes where min and max were not properly
  initialized.
* Added testing command to makefile.
Updated EqualATypes to return the first differing index.

* Returns both the the equality and the first differing index.
Added Float64sFromATypes for unchecked conversion to float64.
Switched order of return types for FindAType.

* Put whether the value was found before the index of the value to match
  other API, e.g. (min, index), (equal, index).
* Also, whether the value was found determines the validity of the index
  so it makes sense for it to go first.