prep CHANGES for the next release of calc

Author: lcn2

CHANGES

@@ -5,6 +5,9 @@ The following are the changes from calc version 2.15.0.7 to 2.15.1.0:
     The command `git diff -w` reports no changes.  There is no
     functionality change in calc: only ASCII tabs to ASCII spaces.
 
+    Fixed trailblank.  It was pruning . in its find search.
+    Added check for ASCII tabs is non-Makefiles.
+
     This version will form the basis for the calc v2 to calc v3 fork.