v0.2.6: Merge pull request #158 from SciRuby/157_google_chart

Google chart were not loading because URL deprecated

Initial release

Features:

• Generate Plot using Nyaplot, google_visualr, lazy_high_charts gem with more features.

• Generate Tables using Google Charts DataTable and daru-data_tables with features like pagination, sorting by column, option to choose number of rows to be displayed.

• Plotting can be done in IRuby notebook as well as any ruby web application
  framework.

• Data can be in Daru::DataFrame, Daru::Vector, array of array data or
  according to the formate described in Google Charts tool, Highcharts.

• User can use all the features already present in google_visualr,
  lazy_high_charts, nayplot by accessing the respective object using
  #chart and tables using #table.

• The article written about initial features briefly : https://github.com/shekharrajak/daru-view/wiki/All-about-daru-view