ENH : replace cout text for readImageITK and readMapITK

- two cout were still displaying readFileITK in VectorImageUtils.txx
BUG : correct calatkLDDMMTests failing

- Issue is with StepLengthSelection Solver :linesearch stopped for bad value of displacement (sometimes 0???). Why are those values so small? error physic/relative? (if yes should multiply the value by the spacing!)
- Also, should NOT exit on first try if displacement too small, but seemed like it was doing it
- This does not fix the StepLengthSelection issue, it just specifies the old Solver to be used (LineSearchUnconstrained)