Corrected bug with Integer param where default=None was not being allowed even when allow_None was set. Moved bounds checking in Number type into its own method (_checkBounds) to provide a minimum override for _check_value.
Corrected bug with Integer param where default=None was not being allowed even when allow_None was set. Moved bounds checking in Number type into its own method (_checkBounds) to provide a minimum override for _check_value.

Tasignotas/topographica_mirror,ioam/topographica,mjabri/topographica,Tasignotas/topographica_mirror,Tasignotas/topographica_mirror,mjabri/topographica,ioam/topographica,Tasignotas/topographica_mirror,mjabri/topographica,ioam/topographica,mjabri/topographica,Tasignotas/topographica_mirror,mjabri/topographica,ioam/topographica,ioam/topographica