Excel/html files should be processed directly in tabular module

[blcham]

In Tabular module, we transfrom HTML and Excel files into CSV and then process them using supercsv library. We need to do that directly and not transform it. In order to do that, we need to refactor the code first.

There should be a unified interface to process tabular data using (I guess) the adapter pattern. Try to do little commits to refactor it incrementally.

A/C:

• in tabular module input stream is read only once
• there is unified interface to process tabular data that is easy to understand
• this task may resove also Tabular module does not process '\t' correctly in HTML and XLS files #214