Render TEI annotations

[gythaogg]

This pull request introduces new behaviors and styling rules to handle specific elements in the show_popup.js script and tei.css stylesheet. The changes primarily focus on processing and displaying different XML elements.

Enhancements in element handling:

• Added behavior for lg element to create a quote element and process its child nodes.
• Added behavior for l element to create a div element and process its child nodes.
• Added behavior for unclear element to wrap content in a span with a specific class and display it with parentheses using CSS.
• Added behavior for foreign element to wrap content in a span with a specific class and display it in italics with a title attribute for the language.
• Added behavior to discard milestone elements.

Styling updates:

• Added CSS rules to style foreign elements in italics and wrap unclear elements with parentheses.

fixes #134