Corrected bug by including cmath in adiosFunctions.cpp

Removed helloWriter.cpp and helloDataMan.cpp, now using
helloDataMan_OOP.cpp and helloWriter_OOP.cpp

Tested memory leaks with valgrind for simple example
Verifying if variable index is written correctly

Added ./src/format/BP1Writer.cpp

To do:
Need to test for array index and payload write

Propagate GetType<T> in Group, Engine and Support classes

To do:

Test ./examples/hello/writer/helloWriter_OOP.cpp

BP1Writer: Continue working on functions to write data and metadata

Group: added Dims alias and SetDimensions function, so dimensions can be built from a Var List put in an std::initializer_list<Var>

Added a bool flag in Variable to know if it is a dimension


To do:
Allow for passing values at DefineVariable

rather than handlers

Group&, Method& and the polymorphic std::shared_ptr<Engine> will be
returned by DeclareGroup, DeclareMethod and Open.

Added Group functions DefineVariable to be a template
Now using adios::Var when creating a variable (still a variable name
string).

Uses more C++ OO + templates features

Compiled and tested with ./examples/hello/helloWriter_OOP.cpp , mpi and
no-mpi versions

Run and tested helloWriter under examples/hello/writer
Fixed Makefile

First function argument should name the required:
Buffer type for AddCapsule, e.g. AddCapsule( "Heap", ... );
Transport method for AddTransport, e.g. AddTransport( "POSIX", ... );

This version compiles. 
Tested with 2 write APIs:

under examples/hello/singleBP
helloSingleBP.cpp -> using ADIOS single manager class from ADIOS.h
helloSingleBP.cpp -> using ADIOS objects from ADIOS_OO.h

both generate a .bp file using a POSIX transport

To do:
Test compilation in other platforms/compilers
Add coverage test cases
Add the NULL transport (does nothing)
Work on SingleBP engine to generate bp format
XML config file support (to be defined)