add an 'analyze' makefile target

that just runs the clang analyzer.
shift unsigned numbers.

much better semantics.
netz: use a bool instead of an int for conditional

also explicitly note that we don't care about Barrier's return
value.
debug: be explicit about getting bools from ints.

pleases lint.
static checkers cant figure out this is null.

due to it being on a different rank.  le sigh.
note that return value is ignored.
stop using '%ms' extension in scanf.

just allocate it.  it's convenient, but broken on both Mac and
intel and so we needed the other code paths anyway... might as
well just make them consistent.  bleh.

also start giving string limits on scanf calls, to make sure we
don't overflow our buffers.
use cppcheck in 'analyze' step.