Refs #8519 Fixed warnings and CppCheck errors

Addressed all the Gcc warnings and CppCheck errors i'd introduced in #8509
Refs #8519 numToSkip has to be an int

Changed numToSkip back to int and static_cast it to size_t when the comparison needed to happen.

The reason was the property didn't like being given a non-int
Merge remote branch 'origin/feature/8519_LoadAscii_compiler_warnings'