Altered viennacl custom operations

Version 1.4.0-preview of viennacl requires kernel name parameter for custom
operations.
Removed tabs
Removed const_cast from viennacl operations

This is not required in the latest version
viennacl use default operations unless VIENNACL_WITH_OPENCL is defined
dummy
cont iteratoren
cont iteratoren
cont rewrite iterators
cont const step iterator
cont
const step iterator for steppers finished
const step iterator for steppers finished
small fixed, adding missing included
starting implementing adpative iterators for controlled steppers
added some tests for adaptive iterator with controlled steppers
update todo list
const step time iterator for steppers implemented and tested
adaptive time iterator for controlled steppers implemented
finalized redesign iterators
update todo list