Zemanim, daf yomi, etc.

This is most of what I had in my tree. I cleaned out the PalmOS stuff (good riddance) and some of the more blatantly Android-specific stuff (to be discussed later). Let me know if you need it further untangled into separate pull requests... but the merge/unmerge was looking kind of tricky.

I had added my own separate switches for sunrise/sunset. I have kept both those and the existing switch from the master branch, because both approaches might be useful in different contexts. When printing them along with other zemanim it seems to make more sense to show them in chronological order. Also my Android app intersperses calendar data with the events from Hebcal. 

The "DeclareEvent" function is there to collect events when compiled into another app, but I left it in this commit because it seems like a useful refactoring anyway, reducing some duplicated logic.

Daf Yomi has Hebrew names for only some of the mesechtot. I didn't wind up putting in more because the RTL handling was not working out right on Android in Hebrew mode. Of course it should be fixed at some point, along with Hebrew text for the names of the zemanim.