Fix configure warning and clang/osx failure.
Merge pull request #30 from evoskuil/master

Build warns and fails in configure on clang/yosemite.
Add missing m4 scripts.
Merge pull request #31 from evoskuil/master

Configure checks are missing m4 scripts.
Suppress format security warning (safe in this instance).
Resolve conditional unused parameter warning.
Merge pull request #32 from evoskuil/master

Compiler warnings issued in clang.
Restore structure to targets lost during nonrecursive refactor.