Addressing comments in pull request #475.  Used some boost filesystem
functionality to remove custom code. Added EnvironmentTests file. Other
small tweaks.
astyle rc formatting on files I've recently edited
Merge remote-tracking branch 'robert/find-modules-in-path' into find-modules-in-path
updated findModuleLib's implementation to explicitly look in the cyclus install path first
updated documentation in dynamic module header
small changes and clarifying comments. @rwcarlsen, feel free to let me know why the changes were made in the first place (this is the benefit of issuing the PR to me rather than making it a complete reissue), because it wasn't clear to me
removed extraneous include
updated the module environment variable so that it's only actually written out (in hard code) once. there's now a functional interface for it, so it can easily be changed in the future if need be
updated environment tests to incorporate functional interface of the name of the cyclus module path