CREATE: exceptions.h - custom exceptions header file

Contains BadFilenameException and NullExerciseException
COMPLETE: Testing for BadFilenameException and

NullExerciseException.
WORKING: Adding Exceptions to Shimmer class
BROKEN: beginReadingData method within Shimmer class.

Turns out, it doesn't reset the rep count of the exercise when incrementing
stashing commit
Found problem in code. setExercise method of Shimmer class

calls update, but update will throw an error if there is an invalid filename.

Thus, if you setExercise before setFilename in a Shimmer instance, you'll
have a bad time.
stashing commit. code breaks on testShimmer again. I'm trying

to examine the Shimmer class and clean up the code so that it should only
throw exceptions in the beginReadingData method of Shimmer
Shimmer class working again. Throws a derivative class of

runtime_error if unable to read data from file or if an exercise is NULL.
Also able to specify either the exercise or the filename for the Shimmer
in either order
starting creation on a command line menu system (CmdMenu.h and

CmdMenu.cpp) to work with the program to allow you to select a file & exercise
stashing commit
stashing commit. slight logic error in display method of

CmdMenu.cpp
CmdMenu works except when length 0 or length >= 80
testing CmdMenu display method
still working on display method of CmdMenu class
working on printing title in the display method (CmdMenu)
WORKING: display method on CmdMenu.cpp (line 65)

working on printing each menu option (along with 1) 2) 3) , etc)
centered title working, moving on to centering menu opts
working on display method of CmdMenu class (on line 72)

working on printing menu options longer than one line long
checking display case when there is a long title(CmdMenu)
same as last commit