Fix fish completion when having alias on awk or grep

Docker-DCO-1.1-Signed-off-by: Guillaume J. Charmes <guillaume@charmes.net> (github: creack)

contrib/completion/fish/docker.fish

@@ -26,20 +26,20 @@ end
 function __fish_print_docker_containers --description 'Print a list of docker containers' -a select
     switch $select
         case running
-            docker ps -a --no-trunc | awk 'NR>1' | awk 'BEGIN {FS="  +"}; $5 ~ "^Up" {print $1 "\n" $(NF-1)}' | tr ',' '\n'
+            docker ps -a --no-trunc | command awk 'NR>1' | command awk 'BEGIN {FS="  +"}; $5 ~ "^Up" {print $1 "\n" $(NF-1)}' | tr ',' '\n'
         case stopped
-            docker ps -a --no-trunc | awk 'NR>1' | awk 'BEGIN {FS="  +"}; $5 ~ "^Exit" {print $1 "\n" $(NF-1)}' | tr ',' '\n'
+            docker ps -a --no-trunc | command awk 'NR>1' | command awk 'BEGIN {FS="  +"}; $5 ~ "^Exit" {print $1 "\n" $(NF-1)}' | tr ',' '\n'
         case all
-            docker ps -a --no-trunc | awk 'NR>1' | awk 'BEGIN {FS="  +"}; {print $1 "\n" $(NF-1)}' | tr ',' '\n'
+            docker ps -a --no-trunc | command awk 'NR>1' | command awk 'BEGIN {FS="  +"}; {print $1 "\n" $(NF-1)}' | tr ',' '\n'
     end
 end
 
 function __fish_print_docker_images --description 'Print a list of docker images'
-    docker images | awk 'NR>1' | grep -v '<none>' | awk '{print $1":"$2}'
+    docker images | command awk 'NR>1' | command grep -v '<none>' | command awk '{print $1":"$2}'
 end
 
 function __fish_print_docker_repositories --description 'Print a list of docker repositories'
-    docker images | awk 'NR>1' | grep -v '<none>' | awk '{print $1}' | sort | uniq
+    docker images | command awk 'NR>1' | command grep -v '<none>' | command awk '{print $1}' | sort | uniq
 end
 
 # common options