*) mv HelloWorld.Java HelloWorld.java; Changes will not be visible to git until .git/config->ignorecase is set to false (was true)

*) A banch of changes to Makefile - .PHONY: clean; %.class : %.java instead of Old-Fashioned suffixes; correct way of setting .SUFFIXES - see Makefile comments
-) HelloWorld.Java the last commit was incomlete. It was 'mv HelloWorld.Java HelloWorld.java', but not 'cp HelloWorld.Java HelloWorld.java' how it may look like
Merge pull request #1 from sealemar/master

mv HelloWorld.Java HelloWorld.java; A banch of changes to Makefile