fix grafting

Author: gares

src/coq_elpi_builtins_synterp.mli

@@ -59,7 +59,7 @@ val clause : clause Conversion.t
 type scope = ExecutionSite | CurrentModule | Library
 
 val scope : scope Conversion.t
-val grafting : ([ `After | `Before ] * string) Conversion.t
+val grafting : ([ `After | `Before | `Replace ] * string) Conversion.t
 val options : (Coq_elpi_HOAS.options, Data.constraints) ContextualConversion.ctx_readback
 val locate_module : BuiltIn.declaration
 val locate_module_type : BuiltIn.declaration