Modified today label, removed Javadoc errors, fixed a month selector bug, Joda time integration. Relates to issues #5, #35, #36.

Update:
Provided Joda time integration. More specifically, created getters and setters for the Joda time LocalDate class, and created the Joda time dependency. See commit e1c8c1d and ed94547 for more details.

Update:
Fixed a bug in the month selector pop-up wherein the month selector was not selecting the correct month in certain cases. See commit 9c8f56c for details.
Note, the github diff is showing many changes to the file (possibly due to an OS difference in newline characters?) but the only actual code changes are in AbstractDateModel.setMonth()

Changes:
The today label was not closing the pop-up (like the clear label does),
and it also was not selecting the current date if the date picker was
null. Modified the today label action to fix these things.

Also made minor modifications to a few javadoc entries that were causing
compile errors (failure to compile) under Netbeans and Maven.