Current master not compiling on Mac with clang, and Ubuntu gcc 5

Created by: williamfgc

heat transfer example seems to be broken:

/Users/wfg/workspace/ADIOS2/examples/heatTransfer/write/HeatTransfer.cpp:23:59: error: 
      expected '('
HeatTransfer::HeatTransfer(const Settings &settings) : m_s{settings}
                                                          ^
/Users/wfg/workspace/ADIOS2/examples/heatTransfer/write/HeatTransfer.cpp:23:68: error: 
      expected ';' after expression
HeatTransfer::HeatTransfer(const Settings &settings) : m_s{settings}
                                                                   ^
                                                                   ;
/Users/wfg/workspace/ADIOS2/examples/heatTransfer/write/HeatTransfer.cpp:23:60: warning: 
      expression result unused [-Wunused-value]
HeatTransfer::HeatTransfer(const Settings &settings) : m_s{settings}
                                                           ^~~~~~~~
/Users/wfg/workspace/ADIOS2/examples/heatTransfer/write/HeatTransfer.cpp:24:1: error: 
      expected unqualified-id
{
^
4 warnings and 3 errors generated.