Fix checkstyle warnings
Eclipse formatter: indent with tabs, not spaces
Revert "Fix possible NPE from fcabf976502d2686c4f0c29d046d063d57494ba7"

This reverts commit 62b15bd19af1895dc627a9269b135e7d149ce213. The values
are checked a few lines above, so they can't be null at this point
Remove unused imports
Fix identation/whitespace
Clean up what is defined in build.properties and build.xml

build.properties now defines default values for all the variables that
it would make sense to vary locally, and build.xml defines those that
people should probably not mess with.
Test filtering of multiline header with tabs
Test filtering of unknown header
Merge remote-tracking branch 'zidel/various_patches'

Conflicts:
	test/org/freenetproject/freemail/MailHeaderFilterTest.java