made the pack completely portable and wrote relevent bat files to go with it

gitportable/usr/share/awk/have_mpfr.awk

@@ -0,0 +1,9 @@
+# adequate_math_precision --- return true if we have enough bits
+#
+# Andrew Schorr, aschorr@telemetry-investments.com, Public Domain
+# May 2017
+
+function adequate_math_precision(n)
+{
+    return (1 != (1+(1/(2^(n-1)))))
+}