make DalvikRunner ignore .#Foo.java files

make DalvikRunner ignore .#Foo.java files

Emacs makes hidden bogus symlinks for open modified files such as
".#Foo.java -> user@host.pid:rand" which I'm guessing are to identify
the owning user/host/process. Unfortunately, DalvikRunner was picking
these up as source and trying to compile them.

This change makes NamingPatternCodeFinder ignore these. In order to
avoid duplicating this in all the subclasses, the subclasses now call
super.matches as a first pass. Now subclasses only apply any
additional filtering they want. MainFinder.matches was deleted since
it wasn't adding any new restrictions.

We arguably could add a better starting filter perhaps, but skipping
dot files seems a reasonable first stem.

Change-Id: Ic9f5ec0bb629d5e1bc25a5b80a6619a64285d2b0