feat: creating new mx_ suite of macros!

also adding new mx_getcode macro

tests/base/mp_getcols.test.sas

@@ -0,0 +1,40 @@
+/**
+  @file
+  @brief Testing mp_getcols macro
+
+  <h4> SAS Macros </h4>
+  @li mp_getcols.sas
+  @li mp_assertcols.sas
+  @li mp_assertcolvals.sas
+  @li mp_assertdsobs.sas
+
+**/
+
+
+/* valid filter */
+%mp_getcols(sashelp.airline,outds=work.info)
+
+
+%mp_assertdsobs(work.info,
+  desc=Has 3 records,
+  test=EQUALS 3,
+  outds=work.test_results
+)
+
+data work.check;
+  length val $10;
+  do val='NUMERIC','DATE','CHARACTER';
+    output;
+  end;
+run;
+%mp_assertcolvals(work.info.ddtype,
+  checkvals=work.check.val,
+  desc=All values have a match,
+  test=ALLVALS
+)
+
+%mp_assertcols(work.info,
+  cols=name type length varnum format label ddtype fmtname,
+  test=ALL,
+  desc=check all columns exist
+)