Merge the build system to trunk: ct-ng is now installable:
- ./configure --prefix=/some/place
- make
- make install
- export PATH="${PATH}:/some/place/bin"
- ct-ng <action>

Better handling of the steps lists:
- new make rulle: liststeps,
- new help entry telling about liststeps,
- update documentation accordingly.

Make the progress bar a default for all samples.

Always call distclean after each sample when doing a regtest.

Update version to -svn.

Prepare to release crosstool-ng-0.0.5.

Rework the help system. For now, this is mostly a no-op (it only re-organise the help entries), but later, that may come in handy when we want ct-ng to be installable).

Offer an option to build the gdbserver statically. This helps in case of debugging shared library loading.

The log file is no longer configurable: it is always "${CT_PREFIX_DIR}/build.log".
Add an option to compress the log file upon successfull build.
Make rendering the toolchain read-only optional.
A few eye-candy fixes.

Default the progress bar to 'Y'.