Add error flags to C bindings

Created by: williamfgc

adios2_adios *adios2_init_config(const char *config_file, MPI_Comm mpi_comm, const adios2_debug_mode debug_mode)

replace with: int adios2_init_config(adios2_adios* adios, const char *config_file, MPI_Comm mpi_comm, const adios2_debug_mode debug_mode)

To basically capture the C++11 library exceptions