one more frequency field to remove
Revert "new type Perm_t for permanence"

This reverts commit be20cc616ac076ab13e5aa44024d6c0edd5bfe1a.
Address Scott's comment - use float (= NTA_Real32)
change Synapse.permanence type to NTA_Real32 (=float)

thanks Scott!
make Segment._nCells static

following the doc
bump Segment's version,

as made incompatible by (float) _permanence change
Thanks Subutai
Segment: replace magic '1' with VERSION

for latest version checks
Segment,Cells4: version type changed to NTA_UInt16 (unsigned short)

65536 versions is enought for everybody! ;)
Revert "make Segment._nCells static"

This reverts commit 1f5472decbd717ec6be58af0c6c660e49e80f07a.

compiles, but run_tests.sh fail with multiple:
tests/unit/py2/nupic/research/tp_constant_test.py:32: in <module>
>   from nupic.research import fdrutilities as fdrutils
../../nta/eng/lib/python2.7/site-packages/nupic/research/__init__.py:30: in <module>
>   from nupic.bindings.algorithms import svm_01, svm_dense
../../nta/eng/lib/python2.7/site-packages/nupic/bindings/algorithms.py:6: in <module>
>   import _algorithms
E   ImportError: /home/marek/nta/eng/lib/python2.7/site-packages/nupic/bindings/_algorithms.so: undefined symbol: _ZN3nta10algorithms6Cells46CState7_nCellsE