Add an intentionally ambiguous grammar for testing purposes.

It seems to work fine.

This bumping of version is insignificant.  I just find it notable that
I seem to finally obtain a version without trivial bugs.  Hooray!

This is not of much use right now, but can be helpful later.

In the process of splitting, cloning, and planting the forest, I
forgot to check whether some cloned node of the node inquestion
satisfy the condition.  This used to cause forests that violate some
fundamental assumptions.  Now this is supposed to be fixed, but more
tests await us.

* src/test.c: input is a malloc'ed pointer, which can be NULL due to
  malloc not being able to allocate enough memory.  So I have to guard
  against this possibility.

Aside: Why are some intermediate files added again?

Those were added by accident.

I do not use a tool to automatically format the codes, so sometimes
the codes look ugly.  This commit reformats the codes so that they
look better and shorter on each line.

Now the binding part is finished.

What remains is a bug encountered when planting a fragment to the
forest which intersects a packed node, which would lead to invalid
forests.  This will also cause problem when planting a packed
fragment, but until now my testing grammars do not produce packed
fragments, so this problem is not encountered yet.

I am still figuring out efficient ways to solve this problem.

Add more directories under control of autotools.