Fix build error in commented out code
Excercise 3.2 (first part)
ex 3.2 updates
Exercise 3.3 initial implementation
adding content for ex4.1 into exercise 3.3
tidy up and some changes to interface
finish refactoring
ongoing dev
Remove duplicate code from ex-3.1
Solution to ex3.1
Merge remote-tracking branch 'origin/master' into solution

Conflicts:
	exercise-3-1/src/test/java/com/ltree/carbonandmore/BasicUnitConverterTest.java
Tidy up solution to ex3.1
Solution to exercise 3.2
Ex3.2 back out solution
Check in part solution 3.3
Move log4j properties
Merge branch 'master' into solution

Conflicts:
	exercise-3-3/src/main/java/com/ltree/carbonandmore/dao/XMLEmissionDAO.java
Solution to 3.3
solution for ex4.1