feat: adding mddl_xx series of macros (and tests). Closes #166

ddl/mddl_dc_locktable.sas

@@ -0,0 +1,25 @@
+/**
+  @file
+  @brief Locktable DDL
+  @details For "locking" tables prior to multipass loads. Used by
+      mp_lockanytable.sas
+
+**/
+
+
+%macro mddl_dc_locktable(libds=WORK.LOCKTABLE);
+
+  proc sql;
+  create table &libds(
+      lock_lib char(8),
+      lock_ds char(32),
+      lock_status_cd char(10) not null,
+      lock_user_nm char(100) not null ,
+      lock_ref char(200),
+      lock_pid char(10),
+      lock_start_dttm num format=E8601DT26.6,
+      lock_end_dttm num format=E8601DT26.6,
+    constraint pk_mp_lockanytable primary key(lock_lib,lock_ds)
+  );
+
+%mend mddl_dc_locktable;