ghc isn't clever enough not to stomp on itself when building dependencies. This
change makes the 1 dependency explicit.

It also adds a dependency on src/libguestfs.la.

This change adds an explicit dependency on generator.ml for every file it
generates, except java files. Java is left for another time because it's
considerably trickier.

It also adds a build rule for src/libguestfs.la so it can be rebuilt as required
from other directories.

It does this by creating a top level make file, subdir-rules.mk, which can be
included from sub-directories. sub-directories need to define 'generator_built'
to include local files which are built by generator.ml, and they will be updated
automatically.

This fixes parallel make, and will automatically re-create generated files when
make is run from any directory.

It also fixes the problem which efad4f53 was targetting. Specifically,
src/guestfs_protocol.(c|h) had an erroneous dependency on stamp-generator, and
therefore generator.ml, despite not being directly created by it. This caused
them to be recreated every time generator.ml ran rather than only when
src/guestfs_protocol.x was updated, which cascaded into a daemon and therefore
appliance update.

This patch also changes the contents of the distribution tarball by including
files created by rpcgen.

This commit changes guestfs_launch so that it both launches
the appliance and waits until it is ready (ie. the daemon communicates
back to us).

Since we removed the pretence that we could implement a low-level
asynchronous API, the need to call launch() followed by wait_ready()
has looked a bit silly.

Now guestfs_wait_ready() is basically a no-op.  It is left in the
API for backwards compatibility.  Any calls to guestfs_wait_ready()
can be removed from client code.

* cfg.mk (disable_temporarily): Remove sc_prohibit_trailing_blank_lines.
* appliance/Makefile.am: Remove trailing blank line(s).
* appliance/debian/modules/y0_install-guestfsd: Likewise.
* appliance/make.sh.in: Likewise.
* appliance/packagelist.in: Likewise.
* appliance/update.sh.in: Likewise.
* haskell/run-bindtests: Likewise.
* ocaml/run-bindtests: Likewise.
* python/run-python-tests: Likewise.
* recipes/squashfs.example: Likewise.
* ruby/run-ruby-tests: Likewise.

This patch allows you to do:
mkdir build
cd build
../configure ...
make

This will output all generated files to the build directory. Given that
autogen automatically runs configure, you can also do:

BUILDDIR=./build ./autogen.sh

which will do the right thing.

Also:

* Fix a dependency bug which means that guestfs_protocol.h
  isn't automatically rebuilt.
* Re-running autogen.sh with no arguments won't blow away your previous
  configure arguments.

Git users now require the OCaml compiler in order to regenerate
the generated code after a checkout.

Generated code will remain in the tarball, so users of the
source tarball will not need the OCaml compiler.