add the functionality of FMU export
add INSTALL instructions for ecos
check the md5sum of the ecos package before installation
Remove version number from extern directory name
DOC: README for extern/
EXTERN: Make ECOS URLs consistent, under github.com/embotech
CONTRIB: docstr for robotfmu.py
CONTRIB: fmu example is marked as executable
EXTERN: ecos: Place fetched files under separate dir; quit on error

Two important modifications to the shell script:
1. quit upon error, including missing tools
2. uses `/bin/sh` unless invoked by passing to a shell program.
CONTRIB: fmu Makefile: move extern dirs to vars; only use -lrt on Linux

ECOSDIR and FMIinclude are defined near the top of fmu/Makefile to
point to corresponding directories under extern/ in the TuLiP source
tree.

The `-lrt` switch is only used if building on Linux.  To achieve this,
we use `uname` as in the Makefile for ECOS.

The man page for clock_gettime() indicates that linking `rt` is only
required for earlier versions of glibc.
EXTERN: ecos is built at the time of generating the FMU

...so do not do it in the install.sh script
EXTERN TRIV: Rename to something apropos
EXTERN: DOC, and return error if checksums do not match for ECOS

The intent is that get.sh should only return with success if it
actually had success, which is important if get.sh is used by something
else automatically.

The README file together with error messages or comments in get.sh
should be enough for users with little or no experience with shell
scripting.
EXTERN: Ignore fetched files
CONTRIB: For FMU export, one README to instruct them all.
CONTRIB DOC: Improve docstr style
CONTRIB TRIV: Delete vestigial @tags@
CONTRIB TRIV: Delete unnecessary return statements
DOC: Entry for fmu in contrib/README
TRIV DOC: Be sure readers detect reST formatting