Increase CPPCHECK_DEVMINOR to 68
Make single-argument constructors explicit
Set version to 1.67.99/"1.68 dev" in the remaining places
MathLib: Added test for isDec() and removed not required state.
Reuse previously computed values
Merge pull request #461 from Dmitry-Me/reuseCOmputedValues

Reuse previously computed values
CheckOther::invalidPointerCast: Incorrect interpretation of settings