building gadgetron master is failing on the current VM

[KrisThielemans]

I had a few problems trying to upgrade Gadgetron on my current 2.0 VM

• CMake couldn't find cblas.h, see http://cmake.3232098.n2.nabble.com/find-path-and-double-symbolic-link-td7599980.html. Current lousy work-around

cmake -DCBLAS_INCLUDE_DIR=/usr/include/x86_64-linux-gnu/ .

• recent gadgetron needs libpugixml-dev #139

• As we have doxygen, it requires sphinx, which then complained about missing module breathe. Pending a possibility to disable the documentation, no option to disable building of the documentation gadgetron/gadgetron#778, we need to install this module. For some reason, this wasn't enough

sudo apt install python3-breathe

fix

sudo apt install python3-pip
python3 -m pip install breathe

but this gave me a "service" warning about upgrading libssl1.1 and restarting services, which would break any automatic set-up (but maybe that won't happen when we build a new VM).

Painful.

[KrisThielemans]

sorry. on Ubuntu 18.04, sphinx uses python2, therefore the above lines are incorrect. we currently need for instance

python -m pip install breathe

[KrisThielemans]

@dchansen kindly introduced an Gadgetron option BUILD_DOCUMENTATION defaulting to OFF, so ignore all the sphinx problems as they won't appear anymore.

[paskino]

SyneRBI/SIRF-SuperBuild#438 will possibly close this?

[KrisThielemans]

This is obsolete and needs to be fixed elsewhere anyway. I suggest to close this. Just not sure where to document the -DCBLAS_INCLUDE_DIR solution