Merge branch 'develop'
Release 0.0.3. Babelfish::Data inherits from Quandl::Data
remove quandl_data as a dependency.
Release 0.0.4. remove quandl_data as a dependency
add Quandl::Error::Standard, all errors inherit from Error::Standard
improve error messages with line, row, context
Release 0.0.5. Improved error messages with line numbers, context, row
added frequency guesser