Update makefile's clean target to delete files copied to assets/ and the contents of the install dir
Merge branch 'make_clean' of https://github.com/ddunwoody/scapi into ddunwoody-make-clean
fixed double line in .gitignore added both by david and me in seperate branches
fixed the clean-jni-assets target: the shared jni library extension is different on mac os x
Manual Merge of pull request #7.
Fixed a small issue in the makefile (the correct extension of jni libraries).