Reduced one map in operations
Calculation and Parse input methods are independent of expression evaluator
Expression Parser created which gives back string
Works with expression instead of strings
Tested expression and works fine
Added equals, toString for expression. Removed getValue and used Double.parse where ever it was used earlier.
Added All Operators
Expression evaluate works for single value expression too
Added ValueExpression which can perform an operation on its value
Removed Individual Operators and added one Operator class with all operations. Created Operation expression
Removed Individual Operators and added one Operator class with all operations. Created Operation expression
Introcuded Bracket Expression and parsed expressions inside brackets
added tests for operations with bracket
adding missing source file