Generalize adding of include dirs in make.target.CxxCompiler
Change Tool._translate_abstract_flag() to raise instead of returning None
Generalize adding of libraries and libdirs in make.target.Linker
Consolidate identical Tool._translate_abstract_flag() implementation
Generalize “output path” argument in make.tool.Tool
Consolidate and simplify handling of Tool._m_sOutputFilePath
Change Tool.set_output to write-only property Tool.output_file_path