restore join_string() symbols in library

restore join_string() symbols in library

To keep the library it backward compatible, instantiate versions
of join_string() for STL containers.

Old symbols (x86):

    0003a040 g    DF .text  00000083  Base        _ZN3I2n11join_stringERKSt4listISsSaISsEERKSs
    00039fb0 g    DF .text  00000084  Base        _ZN3I2n11join_stringERKSt6vectorISsSaISsEERKSs

New symbols:

    000aa0fd g    DF .text  00000041  Base        _ZN3I2n11join_stringERKSt4listISsSaISsEERKSs
    000b084d  w   DF .text  0000017d  Base        _ZN3I2n11join_stringISt20_List_const_iteratorISsEEESsT_S3_RKSs
    000b09ca  w   DF .text  0000017d  Base        _ZN3I2n11join_stringIN9__gnu_cxx17__normal_iteratorIPKSsSt6vectorISsSaISsEEEEEESsT_S9_RS3_
    000aa13e g    DF .text  00000041  Base        _ZN3I2n11join_stringERKSt6vectorISsSaISsEERKSs
    000afbce  w   DF .text  00000074  Base        _ZN3I2n11join_stringISt6vectorISsSaISsEEEESsRKT_RKSs
    000a9f62 g    DF .text  0000019b  Base        _ZN3I2n11join_stringEPKPKcRKSs
    000afb5a  w   DF .text  00000074  Base        _ZN3I2n11join_stringISt4listISsSaISsEEEESsRKT_RKSs