dry: get_pkg to download-if-not-exist and untar. and some minor fixes

install pip in recommended way.
tidy: some line-continuation removal, remove some dead code.
apache: get latest apr and apr-util (no longer bundled in 2.4)
Merge pull request #5 from julienaubert/feature/get_pkg_and_fixes

get_pkg to download-if-not-exist and untar. and some minor fixes