calc InsCellCmd enum 5.1.0 change

[Caolán McNamara]

In https://bugs.documentfoundation.org/show_bug.cgi?id=97193 its
reported that the insertion of some vals into the InsCellCmd enum in 
f97beeef352fdd9fd4f157a7a4c4f6af8341cbe6 of...

-        INS_INSROWS,
-        INS_INSCOLS,
+        INS_INSROWS_BEFORE,
+        INS_INSROWS_AFTER,
+        INS_INSCOLS_BEFORE,
+        INS_INSCOLS_AFTER,

caused recorded macros to break/change behaviour in 5.1.0 because the
messy macro recorder stuff can only record the number passed around.

It's trivial to change this so that the old ones go back to their old
original values, i.e.

         INS_INSROWS_BEFORE,
-        INS_INSROWS_AFTER,
         INS_INSCOLS_BEFORE,
+        INS_INSROWS_AFTER,
         INS_INSCOLS_AFTER,
         INS_NONE

But of course anything recorded in 5.1 would then break in any version
with this change.

Should we put these vals back to their historical value or accept the
new values as locked in now ?

C.