Add post_install() for the new seatd/polkit reqs

PKGBUILD

@@ -5,7 +5,7 @@
 pkgname=sway
 pkgver=1.7
 epoch=1
-pkgrel=3
+pkgrel=4
 pkgdesc='Tiling Wayland compositor and replacement for the i3 window manager'
 arch=(x86_64)
 url='https://swaywm.org/'
@@ -15,8 +15,8 @@ depends=(
   'gdk-pixbuf2'
   'json-c'
   'pango'
-  'seatd'
   'pcre'
+  'seatd'
   'swaybg'
   'ttf-font'
   'wlroots'

sway.install

@@ -1,3 +1,21 @@
+post_install() {
+cat << EOD
+Sway requires additional setup for privilege escalation. Without this setup,
+sway will fail to start with session activation permission failures. Choose one
+of the two available options (In alphabetical, not recommended, order):
+
+1. polkit: This will make sway "just work" right after installation but may be
+           a weightier solution than desired.
+
+2. seatd: Already required as a sway dependency, this is a lighter-weight
+          solution but requires some user configuration: Enabling the service,
+          adding your user to the "seat" group, then logging out/in again.
+
+Either option should provide the same functionality/stability. Refer to the
+Sway wiki page for information.
+EOD
+}
+
 post_upgrade() {
 cat << EOD
 Sway's necessary privileges can now be obtained through seatd as well as the