featherpad: import new package, version 0.12.0

FeatherPad is a lightweight Qt5 plain-text editor.
It is independent of any desktop environment and has:
  * Drag-and-drop support, including tab detachment and attachment;
  * X11 virtual desktop awareness;
  * An optionally permanent search-bar;
  * Instant highlighting of found matches when searching;
  * A docked window for text replacement;
  * Support for line numbers and jumping to a specific line;
  * Automatic detection of text encoding;
  * Syntax highlighting for common programming languages;
  * Ability to open URLs with appropriate applications;
  * Session management;
  * Side-pane mode;
  * Auto-saving;
  * Spell checking with Hunspell;
  * Printing;
  * Text zooming;
  * Haiku OS and macOS support.

Packaged in pkgsrc-wip by pin, as part of a broader effort toward
providing all of LXQt and associated utility applications. General
reviews, feedback, and testing of such by gdt@, ng0@, and myself.

(gutteridge)