Minor difficulty with "n" in psVector struct

[calvin.harman@…]

As a feature enhancement...

For simple vectors (Section 3.2 of SDRS dated May 19, 2004) would it be
possible to set the structure member "n" to the value of nalloc when the
psVectorAlloc(...) function is called. It is slightly inconvenient for users to
set this value manually, since some methods that use psVectors require that "n"
be set or they report an error.

Another possibility would be to remove "n" completely from psVector, since
there is no similar construct implemented in the psImage structure.

[eugene]

the default value for n will be nalloc rather than 0. (SDRS changed to match
this default).