Use a plugin to read data files from gem

[ashmaroli]

Hello Michael,
Revisiting this again. Jekyll learnt a few new tricks since the last time I came with a proposal. It will now automatically require a theme's runtime dependencies. Ergo, the end-user doesn't have to add the required plugins to their config file.

Simply having theme: minimal-mistakes-jekyll will call the dependencies as if it were a Ruby program

With jekyll-data, users need not update their data files with the changes you make. It'll be pulled in from the theme-gem itself.
(It's a different story, if users prefer to use custom ui-text strings though)

With this PR

• jekyll-data v1.x
• jekyll 3.5 automatically requires a theme's runtime deps
• jekyll v3.5.0 had bugs. Hence use v3.5.1 and beyond

[mmistakes]

Nice! Thanks for the PR. When I get a chance I just want to give it a quick test and then I think it'll be easily merged in.

[ashmaroli]

Thank you Michael 😃