renamed return-from-home to revert

treated return and revert as keywords

lib/hcl-prv.h

@@ -313,6 +313,8 @@ enum hcl_tok_type_t
 	HCL_TOK_CONTINUE,
 	HCL_TOK_UNTIL,
 	HCL_TOK_WHILE,
+	HCL_TOK_RETURN,
+	HCL_TOK_REVERT,
 
 	HCL_TOK_BINOP,
 	HCL_TOK_IDENT,
@@ -407,6 +409,8 @@ enum hcl_cnode_type_t
 	HCL_CNODE_CONTINUE,
 	HCL_CNODE_UNTIL,
 	HCL_CNODE_WHILE,
+	HCL_CNODE_RETURN,
+	HCL_CNODE_REVERT,
 
 	HCL_CNODE_ELLIPSIS,
 	HCL_CNODE_TRPCOLONS,