Effective C++ comliant code - use initialisation list instead of assignments within the constructor

[rherrmannr]

Fix compiler warning:

Warning ... should be initialized in the member initialization list [-Weffc++]

Change constructor from
Default::Default(){ stateConvVectorPosition = 0 }

to

Default::Default():stateConvVector(0) {}

for all used variables.

see "Effective C++"
Item 4: Make sure that objects are initialized before they’re used.