Wharfie

During some tests with a Dockerfile for check_mk, I implemented a few compatibility commands (EXPOSE, ARG, WORKDIR)

[#7] Support the commands COPY and ENTRYPOINT
- I messed up CMD and ENTRYPOINT

#7 Support the commands COPY and CMD

[#1] Build as non-root user
- use qemu to make non-root build
- needed host tools during build of qemu: all local wharfie tools and qemu-img
- needed host tools when building w/ qemu: tar, python
- biggest limitations:
--- The size of the possible input and output is hardly limitted.
--- The maximum output size is always fully allocated on disk

strip whitespaces from make target name

[#8] experimental implementation of incremental/multi-level build.
Actually it seems as tar has still problems with it. I can't avoid that tar thinks that s.th. is renamed, even if it is not.
In my tests I found no problems, except the warning from tar until now. But I added it as a command line option anyway, to be safe.

By-the-way I fixed the handling of files in ADD a bit.
- URLs are supported now
- Implicite makerules don't interfer anymore with ADD

[#6] Support downloading files

[#4] abort on error

[#5] throw parse error on wrong commands

restructured the main python script into submodules (curently only makefile generation and wharfile actions)

- added copyright statements + licenses

- allow multiple, space separated value of environment variables
- support additional packages, specified via ADDITIONAL_TOOLCHAIN_PACKAGES in toolchains

added rules for 64 bit support

Prepared for the use of fakechroot, which actually failed atm. as I found no way of using it w/o heavily influence the host installation. And doing that would make the whole effort of avoiding root access futil$
But, it cleaned up the make targets pretty much.

- added options to get system info and to clean intermediate files.
- fixed a small issue in the argument parser, so that you can pass a different filename instead of "Wharfile"

Initial import of Wharfie