add a new feautre to make pacman installation possible

src/config.fish

@@ -1,5 +1,14 @@
 function config -d "sets some configuration variables"
 
+    # If this is not set to "yes", snap-pac-uki will not do anything when
+    # executed.
+
+    # This is to make sure that this program can be installed with pacman. If
+    # this wasn't done, pacman would install this program with an default
+    # config, which most likely wouldn't work correctly. Therefore this needs
+    # to be set to "yes" by the user, once they've configured snap-pac-uki.
+    set -g CFG_ENABLED "no"
+
     # A directory where ukis can be built.
     #
     # It is recommended to keep this within /tmp, as the generated data will not

src/snap-pac-uki.fish

@@ -151,6 +151,11 @@ function main
     config
     check_deps
 
+    if test "CFG_ENABLED" != "yes"
+        echo "not enabled in config file" 1>&2
+        exit 0
+    end
+
     switch $argv[1]
         case "snapshots"
             find_tasks