improve readme

README.md

@@ -11,15 +11,21 @@ Documentation
 =============
 More complete documentation can be found on [Read The Docs](https://strpackjl.readthedocs.org/en/latest/).
 
-Incompatible change in 0.6
-==========================
+Incompatible change for Julia v0.6
+==================================
 
 Note that the primary artifact of this package was the `@struct` macro. In Julia `v0.6`, `struct` is now a reserved word.
 This necessitates a change, hence the macro is now called `@str`. This change has been made since `v0.2.0` of this package.
-This means that any code that uses this package must be changed when running on Julia v0.6. 
+This means that any code that uses this package MUST be changed when running on Julia v0.6.
+
+This will typically require a v0.6-and-above only release of any package that is a dependency of this package. If you must
+support both Julia v0.5 and v0.6 in the same version, you'll have to have version-dependent code in your package; I would
+not recommend doing that.   
+
+Users on Julia `v0.5` can continue to use `v0.1.0` of this package without issues. 
 
 WARNING
 =======
 
-This package is only semi-maintained. While it has been updated to work without warnings on Julia 0.5,
+This package is only semi-maintained. While it has been updated to work without warnings on Julia 0.6,
 there are no guarantees of correctness beyond the existing package tests. Use at your own risk.