[QBS] propose to separate the linker part from cpp module.

[罗勇刚(Yonggang Luo)]

because the linker is an commonly used module, not only cpp module use
that, but also
other module will use that, for example, d programming language,
assembly language,

also, the library should belong's to the linker, the linker's input is
a set of object files along with a set of libraries. the link output
will be a library /dll or a executable.

-- 
         此致
礼
罗勇刚
Yours
    sincerely,
Yonggang Luo