__file: implement --state exists

Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>

cdist/conf/type/__file/gencode-local

@@ -27,7 +27,7 @@ exists="$(cat "$__object/explorer/exists")"
 
 [ "$state_should" = "exists" -a "$exists" = "yes" ] && exit 0 # nothing to do
 
-if [ "$state_should" = "present" ]; then
+if [ "$state_should" = "present" -o "$state_should" = "exists" ]; then
    if [ -f "$__object/parameter/source" ]; then
       source="$(cat "$__object/parameter/source")"
       if [ "$source" = "-" ]; then

cdist/conf/type/__file/gencode-remote

@@ -26,7 +26,7 @@ state_should="$(cat "$__object/parameter/state")"
 exists="$(cat "$__object/explorer/exists")"
 
 case "$state_should" in
-   present)
+   present|exists)
       # No source? Create empty file
       if [ ! -f "$__object/parameter/source" ]; then
          if [ "$exists" = "no" ]; then