feat: creating new mx_ suite of macros!

also adding new mx_getcode macro

tests/base/mp_ds2squeeze.test.sas

@@ -0,0 +1,44 @@
+/**
+  @file
+  @brief Testing mp_ds2squeeze.sas macro
+
+  <h4> SAS Macros </h4>
+  @li mf_getvarlen.sas
+  @li mp_assert.sas
+  @li mp_assertscope.sas
+  @li mp_ds2squeeze.sas
+
+**/
+
+data big;
+  length my big $32000;
+  do i=1 to 1e4;
+    my=repeat('oh my',100);
+    big='dawg';
+    special=._;
+    missn=.;
+    missc='';
+    output;
+  end;
+run;
+
+%mp_assertscope(SNAPSHOT)
+%mp_ds2squeeze(work.big,outds=work.smaller)
+%mp_assertscope(COMPARE)
+
+%mp_assert(
+  iftrue=(&syscc=0),
+  desc=Checking syscc
+)
+%mp_assert(
+  iftrue=(%mf_getvarlen(work.smaller,missn)=3),
+  desc=Check missing numeric is 3
+)
+%mp_assert(
+  iftrue=(%mf_getvarlen(work.smaller,special)=3),
+  desc=Check missing special numeric is 3
+)
+%mp_assert(
+  iftrue=(%mf_getvarlen(work.smaller,missc)=1),
+  desc=Check missing char is 1
+)