Introduce DataBufferFromDataFile Class

[jijoongmoon]

In order to handle various input generation cases, make DataBuffer
Class is base class and inherit this, several children classes is
introduced.
. DataBufferFromDataFile
. DataBufferFromCallback : NYI
. DataBufferFromFramework : NYI
. others. : NYI

Self evaluation:

1. Build test: [X]Passed [ ]Failed [ ]Skipped
2. Run test: [X]Passed [ ]Failed [ ]Skipped

Signed-off-by: jijoong.moon jijoong.moon@samsung.com

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[zhoonit]

How about making a class-bound function(classmethods in java, python, static member function in c++??) to initiate DataBuffer buffer instead of inheriting data buffer by source of databuffer?

If initiating part is going to be lengthy, I think a factory can be used instead for this purpose.

eg.

  DataBuffer dataBufferFromFile = DataBuffer::fromFile('some file path.dat') 
  DataBuffer dataBufferFromFramework = DataBuffer::fromFramework('some framework??')

[jijoongmoon]

I think the DataBuffer class would be too long if it is member function. Also there is possibility to add more DataBuffer ( may be nnstreamer pipe line buffer )

How about making a class-bound function(classmethods in java, python, static member function in c++??) to initiate DataBuffer buffer instead of inheriting data buffer by source of databuffer?

[zhoonit]

Looks good to me ;)