Best effort dependency resolution

Add a new check_install function that checks if a tool is installed and
tries to install it on a best effort basic. Modify all scripts that
benefit from it. Small indentation and correctness fixes.

	modified:   functions/7za.fish
	modified:   functions/alert.fish
	new file:   functions/check_install.fish
	modified:   functions/lscmd.fish
	modified:   functions/rchmod.fish
	modified:   functions/renlow.fish
	modified:   functions/rlsxattr.fish
	modified:   functions/rsdos.fish
	modified:   functions/rsmac.fish
	modified:   functions/rsxattr.fish
	modified:   functions/uz.fish

1 files changed, 18 insertions, 16 deletions

diff --git a/functions/alert.fish b/functions/alert.fish
index 6ab53cb..a21deac 100644
--- a/functions/alert.fish
+++ b/functions/alert.fish
@@ -1,22 +1,24 @@
 function alert --description 'Report status of command to desktop'
-  set -l cmd $argv
-  set -l cmd_str (string join ' ' $cmd)
-  set -l output (eval $cmd 2>&1)
-  set -l retval $status
 
-  if functions -q notify
-    if test $retval -eq 0
-      notify "✅ Done: $cmd_str" "$output"
-    else
-      notify "❌ Failed $cmd_str" "$output"
-    end
+set -l cmd $argv
+set -l cmd_str (string join ' ' $cmd)
+set -l output (eval $cmd 2>&1)
+set -l retval $status
+
+if functions -q notify
+  if test $retval -eq 0
+    notify "✅ Done: $cmd_str" "$output"
+  else
+    notify "❌ Failed $cmd_str" "$output"
+  end
+else
+  if test $retval -eq 0
+    printf "✅ Done: %s\n%s\n" "$cmd_str" "$output"
   else
-    if test $retval -eq 0
-      printf "✅ Done: %s\n%s\n" "$cmd_str" "$output"
-    else
-      printf "❌ Failed: %s\n%s\n" "$cmd_str" "$output"
-    end
+    printf "❌ Failed: %s\n%s\n" "$cmd_str" "$output"
   end
+end
+
+return $retval
 
-  return $retval
 end