[type/__update_alternatives] Fix for non-English locales

Since update-alternatives(1) is localized, screen scraping its output breaks
if the locale is set to non-English.

cdist/conf/type/__update_alternatives/explorer/alternatives

@@ -1,4 +1,4 @@
 #!/bin/sh -e
 
-update-alternatives --display "${__object_id:?}" 2>/dev/null \
-    | awk -F ' - ' '/priority [0-9]+$/ { print $1 }'
+LC_ALL=C update-alternatives --display "${__object_id:?}" 2>/dev/null \
+| awk -F ' - ' '/priority [0-9]+$/ { print $1 }'

cdist/conf/type/__update_alternatives/explorer/path_is

@@ -1,7 +1,8 @@
 #!/bin/sh -e
 
-path_is="$( update-alternatives --display "${__object_id:?}" 2>/dev/null \
-    | awk '/link currently points to/ {print $5}' )"
+path_is=$(
+    LC_ALL=C update-alternatives --display "${__object_id?}" 2>/dev/null \
+    | awk '/link currently points to/ { print $5 }')
 
 if [ -z "$path_is" ] && [ -z "${__cdist_dry_run+dry run}" ]
 then