Add .what() to error message when standard exception is raised in CHECK.
Add .what() to error message when standard exception is raised in CHECK_EQUAL.
Add .what() to error message when standard exception is raised in CHECK_CLOSE.
Refactor common logic for CHECK tests into a fixture and add separate tests for std::exception and non.
Improve CheckFixture method names.

Rename `CheckFixture::Throw` to `CheckFixture::PerformCheckWithNonStdThrow`.
Rename `CheckFixture::StdThrow` to CheckFixture::PerformCheckWithStdThrow`.
Refactor TestExceptions CheckEqual tests to use a fixture and add additional tests for std:: exceptions.
Refactor TestExceptions CheckClose tests to use a fixture and add additional tests for std:: exceptions.
Add .what() to error reporting for std::exceptions in CHECK_ARRAY_CLOSE.
Add .what() to error reporting for std::exceptions in CHECK_ARRAY_EQUAL.
Add .what() to error reporting for std::exceptions in CHECK_ARRAY2D_CLOSE.
Group all exception tests into suites and normalize indentation.
Merge pull request #33 from pjohnmeyer/addingWhatToCheckMessages

Add .what() to check messages for unhandled std::exceptions.

Adds a `UT_CATCH(std::exception...)` block to:

    CHECK
    CHECK_EQUAL
    CHECK_CLOSE
    CHECK_ARRAY_CLOSE
    CHECK_ARRAY_EQUAL
    CHECK_ARRAY2D_CLOSE

Closes #11.