Move transformations into own directory

Move all transformations into their own directory. CMakeLists are
adjusted accordingly.

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@203607 91177308-0d34-0410-b5e6-96231b3b80d8
(cmake) rename polly's shared lib.

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@203608 91177308-0d34-0410-b5e6-96231b3b80d8
Refactor Polly's Pass creation and initialization.

Rename some files and adjust cmake accordingly

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@203609 91177308-0d34-0410-b5e6-96231b3b80d8