Issue 16
Fixes #16
Merge branch 'seanmason-issue-16' of https://github.com/seanmason/math-fun into seanmason-seanmason-issue-16

Conflicts:
	src/com/swtanalytics/math/Fraction.java
	src/com/swtanalytics/math/MathFunction.java
	src/com/swtanalytics/math/Term.java
Merge branch 'seanmason-issue-16' of https://github.com/seanmason/math-fun into seanmason-seanmason-issue-16

Conflicts:
	src/com/swtanalytics/math/Fraction.java
	src/com/swtanalytics/math/MathFunction.java
	src/com/swtanalytics/math/Term.java