Quit immediately if Boost cannot be found. Closes #785.
Make sure the build really is out of source.

Previously it could be fooled if the source and binary
directories were exactly the same.

Also prompt the user to delete the cmake cache, which
will get generated in the wrong place and then confuse
future builds if they ever try to do an in-source build.
Closes #795.
The rigid member could be the first particle we inspect.

Closes #782.
Newer versions of HDF5 name their DLLs differently.
Update for new HDF5.
Many Macs don't have a right mouse button.
Don't try to use an external RMF.

Most likely the external library won't be compatible with
current IMP, and the configure checks don't look for the
external library's SWIG interface files, so building IMP.rmf
with fail with a "can't find RMF.i" error. Closes #798.
Don't update submodules every time we run cmake.

Updating submodules throws away any changes made to them (e.g. PMI)
making work on a development version of PMI rather difficult.
Closes #799.
Only run setup_git for git checkouts.
Work with old Pythons.
Get RMF containing boost version and SWIG fixes.
BOOST_NO_CXX11_RANGE_BASED_FOR didn't appear in boost until 1.53.
Fix PoseScore to match that used by the web server.
Fix variable name.