Revert "Sharpened FilterLineItr tutorial, added ExceptionUtil"

This reverts commit 7480972127e94ef28a3ac84884153632b3babe9d.

Conflicts:
	examples/com/github/xbn/examples/linefilter/IterateKeptLines.java

	examples/com/github/xbn/examples/linefilter/PrintAllJavaDocBlockStartAndEndLineNumsViaDebugging.java
	src/com/github/xbn/xbnjava_overview.html
	test/com/github/xbn/test/ExampleCodeOutputsContain_Unit.java
	z_build/ant_sub_files/javadoc.xml