use synapse_t and NTA_Real32
testutils: use return False immediately

return right away, instead of carrying a result=false value all over,
this is helpful to see what part of the check method errored.
must be float, to avoid early rounding/casting errors

eg: char/char=0, but char/float=0.3 ...
exit early in sameSegment test
fdrutilities: sameSegment() do not fail on zero synapse permanence

don't fail if segment contains synapse with <= 0 permanence,
please review this!