Gulp Pug Versions Save

Changes:

• Allow data to be passed from upstream through the data attribute on a vinyl object. - @colynb

Changes

• Allow Jade version range from 1.1.x through 1.3.x
• Fix tests that weren't working and remove old fixtures

Changes

• Don't wrap errors from Jade compilation in another Error object - imlucas
• Add tests for Jade compilation errors - houkanshan

Changes:

• Jade compilation errors no longer crash the process and only emit an error on the stream. - houkanshan

Changes:

• Jade 1.1 introduced filenames in warnings.
• No longer support streaming file contents.
• Switched to through2 as per Gulp 3.4 guidelines, which breaks node 0.8 compatibility.
• Added documentation about options.
• Small amount of code cleanup.

Jade 1.0 states that it doesn't support node 0.8 anymore. All the tests pass, but I did a minor release incase Jade broke something.