Two makefiles that build either an executable, or an executable and a library from c++ code, using gcc.
Assumes that every header file is contained in a directory called include and use .h as the file extension.
All implementation files must be in src and have a file extension of .cxx
This can be customised by changing the variables at the top of the file
Type make and all executables will be built, otherwise type make <your_executable_name> and that executable alone will be created.