Remove conditionals for composer installation

Composer will be the default way to install CakePHP so don't include
fallbacks.
Move files into top level directory.

These files are not 'code' files and should be at the top level
directory with similar files.
Update config file to reference new VERSION.txt location.
Update TMP constant in tests.

Since CakePHP will no longer have an App directory with it we should not
assume App/tmp will exist. Instead use the system's tmp directory to do
our tests with.
Fix many of the failing tests caused by not using App/tmp anymore.
Update the ProjectTask tests to make them pass.

Update the TestApp routes so ProjectTask can copy and modify them.