Move and rename all files

This commit moves around most files. The new directory structure is as
follows:

* `lib/$LIBRARY/`: contains a library, i.e., a set of `.cpp` files used
  by multiple libraries/tools.
* `include/revng/$LIBRARY/`: contains the public headers associated to
  the library in `lib/$LIBRARY/`.
* `tools/$TOOL/`: directory where all the `.cpp` files (and private
  headers) for a tool reside. Currently we have two tools: `revamb` and
  `revamb-dump`.

On top of this, all file names are now in camel case.

tests/Unit/stackanalysis.cpp

@@ -11,7 +11,7 @@ bool init_unit_test();
 #include <boost/test/unit_test.hpp>
 
 // Local includes
-#include "intraprocedural.h"
+#include "Intraprocedural.h"
 
 using namespace StackAnalysis;