UPSTREAMABLE: src/msio/scalarcolumniterator.h: greater API compatibility

Some versions of casacore replace the ROScalarColumn class with a
simple #define to ScalarColumn, which turns the overloaded method into a
compile error. Avoid this problem.
CHATTER: src/aoflagger.cpp: uniform spacing of percentage output
CHATTER: src/aoflagger.cpp: progress reporting all on one line
CHATTER: src/strategy/actions/baselineselectionaction.cpp: quieter
CHATTER: src/aoflagger.cpp: no long startup message
CHATTER: add 'quiet' option
BUILDHACK: more compat with NRAO casacore