Non-flat directory structure

* Find*.cmake in module directory
* files that are meant to be used as in "include(something.cmake)" in script directory
Test using cookoff as external project
Adding FFTW3 with components

Closes #1
Blank space modifications
Adding test for looking up GreatCMakeCookOff

Currently downloads this branch.
Moving functionality from purify.

Goes towards UCL/purify#5
Have TestCMake use cmake argument parser
Create recursive assert tests in cmake

Have self lookup test use it
Adding TargetCopyFiles to cookoff

Still goes some way towards UCL/purify#5
Removing debug code
wrong argument parsing in TargetCopy
Standardized FindJulia.cmake
Merge branch 'refactor' of github.com:UCL/GreatCMakeCookOff into refactor
Eigen only fails if required
Replace CONFIG with NO_MODULE

Makes it more usable by older versions of cmake.
Mac-enforced spelling error
Still trying to fail on eigen only if required
extra endif
Add version and git reference functions
wrong variable set in gitref function