Add support for parsing rel attributes

Rename variables in parse-h for consistency

Give split-classes a clearer name

Refactor selectors using set = union syntax

Refactor parsers using expression-threading

Refactor reducers for easier testing

Don't error when missing :attrs/:class

Add e-* parsing

Rename get-*-property functions to get-*-value

Add tests for classes-to-props

Add basic support for dt-* parsing

Fallback to text content if attributes are not found

Test smaller units of code

Remove unnecessary comment

Add u-* parsing capability

Re-format trailing parentheses

Add support for parsing empty br/hr tags

Get correct property value for special tags

Set initial REPL/run namespace

Use class name for property keywords

Expand selectors to match classes with prefixes

Create test & implementation for p-name parsing

Create initial test and implementation

Initial commit.