Log Message:
Updated ruby22-roo to 2.7.1.

## [2.7.1] 2017-01-03
### Fixed
- Fixed regression where a CSV's encoding was being ignored \ 
[372](https://github.com/roo-rb/roo/pull/372)

## [2.7.0] 2016-12-31
### Fixed
- Added rack server for testing Roo's download capabilities \ 
[365](https://github.com/roo-rb/roo/pull/365)
- Refactored tests into different formats \ 
[365](https://github.com/roo-rb/roo/pull/365)
- Fixed OpenOffice for JRuby [362](https://github.com/roo-rb/roo/pull/362)
- Added '0.000000' => '%.6f' number format \ 
[354](https://github.com/roo-rb/roo/pull/354)
- Add additional formula cell types for to_csv \ 
[367][https://github.com/roo-rb/roo/pull/367]

### Added
- Extracted formatters from Roo::Base#to_* methods \ 
[364](https://github.com/roo-rb/roo/pull/364)

## [2.6.0] 2016-12-28
### Fixed
- Fixed error if sheet name starts with a slash \ 
[348](https://github.com/roo-rb/roo/pull/348)
- Fixed loading to support files on ftp [355](https://github.com/roo-rb/roo/pull/355)
- Fixed Ruby 2.4.0 deprecation warnings [356](https://github.com/roo-rb/roo/pull/356)
- properly return date as string [359](https://github.com/roo-rb/roo/pull/359)

### Added
- Cell values can be set in a CSV [350](https://github.com/roo-rb/roo/pull/350/)
- Raise an error Roo::Excelx::Extractor document is missing \ 
[358](https://github.com/roo-rb/roo/pull/358/)