This patch adds a combo box at the top of the plugin manager's install panel that lets the user filter the plugin list by category, and is a good first step to making the plugin list less intimidating for those not completely familiar with it. The list of category names is generated dynamically the first time the plugin model is updated, defaulting to "All." Selecting a category refreshes the list to display only plugins from that category.
In addition to this, I would like to pitch an idea for re-naming "Java-Centric" and "HTML & XML" to "Language Support: Java" and "Language Support: HTML & XML" respectively, and add subcategories to the other Language Support plugins. How difficult would it be to rename these? Having a single filter-able category for language support would be nice, and the preference enjoyed by HTML/XML and Java tends to overshadow jEdit's language versatility.