javadocs

I also made a few changes to TimeData's implementation of compareTo and
had it implement Comparable interface
checkstyle fixes
Merge branch 'master' into pmd

Conflicts:
	src/com/so/sofinances/activities/AddTransactionActivity.java
	src/com/so/sofinances/handler/AccountHandler.java
	src/com/so/sofinances/model/Currency.java
	src/com/so/sofinances/model/TimeData.java
	src/com/so/sofinances/model/User.java