Fix T39635: Crash convening curve to mesh
Code cleanup: remove paranoid NULL check
Matcaps.

Instead of setting color every time, just set it on material enable.
Handles all cases of surfaces. Thanks to Campbell for pointing out!
Mempool: delay allocating an initial chunk, its not always used
BMesh: minor speedup, avoid calloc+assign, assign all members instead
BMesh: bmesh_sfme now initializes the copy
Mempool: simplify memory chunk list building
DerivedMesh: replace edgehash with edgeset
Dyntopo: replace GHash with GSet, saves some memory
GHash/Edgehash: make simple iterator checking functions inline.

also remove NULL check, only a few areas made use of this.