Version 1.15.3
* Fix zombie processes when reading proxy settings
* Better error reporting during note parse (Guido Günther)
* Documentation: additional add-in pages, pinning, deleting notes (Sindhu S)
* Use xz compression for dist tarballs
* Flush to disk on note save (Alex Tereschenko)
* Windows: GTK#, .NET installer improvements (Alex Tereschenko)
* Translation updates: cs, es, gl, id, lv, pl, pt_BR