Modification of the Shapes.h file.

Corrected a number of syntax errors, such as statement terminators and
rearranging the typedef.

Also, implemented the isOdd and isEven functions.

Program compiles.
Modification of the Makefile.

Made the default make target print out the targets of the makefile.
Works by grepping through the makefile for '#-' while ignoring lines
with grep in it.

The lines preceding the targets have the '#-' at the start, followed by
the usage of that target.

Added in a build target that simple compiles the project.