sorting table with rowspan cells

fixes #109

updated usage to 2.0 syntax in readme

fixes #91

updated version to 2.0.0

added version info into js and css files

correct parsing of column number

Update bower.json

Update bower.json

fixed - mainsort larger than colspan

fixed a possible issue, if the mainsort would be set outside of the
colspan
in this case, the last cell will be used

Update bower.json

Update README.md

Version 1.8.0