[Add] Create a new branch for Java Doc
Add java doc to Division class
Check author to project name
[UPDATE] added java doc for classes
[UPDATE] added java doc for ExpressionTree class
Add java doc to multiplication class
Add java doc to Subtraction class
Add java doc to Addition class
[Add] Java Doc for TrigoOperator, Sine, Cosine [Still Working]
update java doc
[Add] Java doc for Sine, Cosine, Tangent
add test case for sin cos tan
[UPDATE] added java doc for classes
[Add] Test Case for Sine, Cosine, Tangent
[Add] test case of Csc, Sec, Cot
[Add New Branch] Operator for Csc Sec Cot [Just start]
[Add] Cosecant Operator
[Add] Secant class
[Add] Cotangent class
Merge commit 'f8245c5ad1a2d80f7be7a62701f5dbc63d5c04ab' into develop

Conflicts:
	src/cal/ExpressionTree.java
	src/testCal/ExpressionTreeTest.java