Test Cases rewritten

Test cases rewritten for succinctness
Fraction Modified + Test Casts Added

Added test cases for Divide and constructor class returned to original
Print Modified, absValue + Tests added

Print now shows fractions with denominator of 1 as whole numbers, and
abs is now in place and working.
FractIionCalculator Basics

Created fields and constructors only
Dummy constructor

Created dummy constructor for testing purposes, as well as a calculate
function which will need a case/switch added to i.
Calculate - Add included

Added function to recognise symbols and perform. Addition is now in and
working.
Calculate function added

FOr all transitive functions
Absolute & Negate added