Allow fullprivileges command flag

This commit allows the "+"(fullprivileges) command flag along with
"-" and "@" flags.

lenses/systemd.aug

@@ -72,8 +72,8 @@ let sto_value = store /[^# \t\n]*[^# \t\n\\]/
 let value_sep = del /[ \t]+|[ \t]*\\\\[ \t]*\n[ \t]*/ " "
 
 (* Variable: value_cmd_re
-   Don't parse @ and - prefix flags *)
-let value_cmd_re = /[^#@ \t\n\\-][^#@ \t\n\\-][^# \t\n\\]*/
+   Don't parse @, - and + prefix flags *)
+let value_cmd_re = /[^#@+ \t\n\\-][^#@+ \t\n\\-][^# \t\n\\]*/
 
 (* Variable: env_key *)
 let env_key = /[A-Za-z0-9_]+(\[[0-9]+\])?/
@@ -111,11 +111,12 @@ let entry_multi  = entry_fn entry_multi_kw
                        . Build.opt_list entry_value value_sep )?
 
 (* View: entry_command_flags
-   Exec* flags "@" and "-".  Order is important, see systemd.service(8) *)
+   Exec* flags "@", "-" and "+".  Order is important, see systemd.service(8) *)
 let entry_command_flags =
-     let exit  = [ label "ignoreexit" . Util.del_str "-" ]
+     let fullprivileges = [ label "fullprivileges" . Util.del_str "+" ] 
+  in let exit  = [ label "ignoreexit" . Util.del_str "-" ]
   in let arg0  = [ label "arg0" . Util.del_str "@" ]
-  in exit? . arg0?
+  in fullprivileges? . exit? . arg0?
 
 (* View: entry_command
    Entry that takes a command, arguments and the optional prefix flags *)

lenses/tests/test_systemd.aug

@@ -370,3 +370,12 @@ test Systemd.lns get "[Service]\nExecStart= /usr/bin/find\nEnvironment=  TERM=li
       { "command" = "/usr/bin/find" } }
     { "Environment"
       { "TERM" = "linux" } } }
+
+(* Test: Systemd.lns
+     + and - are OK for command prefixes *)
+   test Systemd.lns get "[Service]\nExecStart=+-/bin/echo\n" =
+     { "Service"
+       { "ExecStart"
+         { "fullprivileges" }
+         { "ignoreexit" }
+         { "command" = "/bin/echo" }} }