Feature/uikit refactor

[bmuenzenmeyer]

Closes #811

Summary of changes:

UIKits are a new term in the Pattern Lab Ecosystem, attempting to evolve beyond the current Styleguidekit pattern which separated front-end templates from front-end assets like stylesheets and code. The existing styleguidekit-assets-default and styleguidekit-mustache-default have merged into uikit-workshop (more on that name in a bit). The hope is that by co-locating all front-end files in a single repository, users will be more capable of altering existing UIKits, making their own, even building multiple UIs from a single source of truth.

You heard that right - Pattern Lab 3.X will support multiple UI outputs from a single set of source patterns - implementing what @bradfrost coined the workshop and the storefront. True to form, the default Pattern Lab experience is therefore the workshop.

patternlab-config.json has a new key:

+  "uikits": [
+    {
+      "name": "uikit-workshop",
+      "outputDir": "",
+      "enabled": true,
+      "excludedPatternStates": ["inreview"],
+      "excludedTags": []
+    }
+  ]

uikits accepts and array of UIKit objects, shipping with the one above.

• name: the name of the UIKit
• outputDir where to output this UIKit relative to the current root. by leaving this empty we retain the existing behavior, outputting to <project_rooter>/public. If you had multiple UIKits, however, you would provided different values, such as:

"uikits": [
  {
    "name": "uikit-workshop",
    "outputDir": "workshop",
    ...
  },
  {
    "name": "uikit-storefront",
    "outputDir": "storefront",
    ...
  }
]

check the output:

• enabled: quickly turn on or off the building of this UIKit
• excludedPatternStates: tell Pattern Lab not to include patterns with these states in this UIKit's output
• excludedPatternTags: tell Pattern Lab not to include patterns with these tags in this UIKit's output
  • currently not supported

Other notes that coincide with this work:

• the default paths.source object paths within patternlab-config.json are now relative to the current UIKit. See the structure of uikit-workshop for more info
• the default paths.public object paths within patternlab-config.json are now relative to the current UIKit's outputDir. Absolute paths will no longer work. Someone could test putting an absolute path in a UIKit outputDir property and see what happens I suppose.
• dependencyGraph.json has moved to the project root rather than public/ as we should only retain one

To aide in users building their own UIKits, I've also created uikit-bare outside this monorepo, as a thing to fork and change to your needs. The uikit-bare wiki attempts to document the API Pattern Lab expects from a UIKit and what data it provides a UIKit during build.

Known Issues

• UIKit excluded tag support
• UIKit lineage still links to excluded patterns

Feedback Needed

This is a work in progress, so please provide feedback along the way.

[coveralls]

Coverage increased (+5.8%) to 69.394% when pulling 87c9d0d on feature/uikit-refactor into 170a11d on dev.

[bradfrost]

Just stopping in to say hello, as this looks fun and interesting!