Changed the java module to allow better control of where the various output goes.
Made building static libs threadsafe.
Some utils modifications.
Added weak_module() so you can load a module for configuration without causing its post_rules() method to be run.
Renamed emk.build() to emk.autobuild().
Fixed bug in _module()
Added subproj loading so you can configure a directory tree with scope overloading.
Changed _load_parent_scope() to be more efficient.
Changed some dict lookups to use get() instead of testing with 'in' first.
In the copy file rule, always run the rule, but mark the target as untouched if the files are identical.
Modified the caching strategy. Added the ability to modify the function to check whether something has changed (on a per-rule basis, if desired)
Added env argument to utils.call()
Merge branch 'master' of https://github.com/kmackay/emk
Fixing missing caches.
Changed allow_nonexistent to weak_depends so that the dependency model is clearer.
Fixed dev stacks mode.
Removed printing.
Fixed caching strategy some more.
Doubled the default number of threads.
Fixed thread count option; made cache entries only be created when needed; fixed some bugs.