add a note on compatibility

Author: bicycle1885

README.md

@@ -32,6 +32,14 @@ julia -e 'using Pkg; Pkg.add("EzXML")'
 This package depends on [libxml2](http://xmlsoft.org/) 2.9.9, which will be automatically installed as an artifact via [XML2_jll.jl](https://github.com/JuliaBinaryWrappers/XML2_jll.jl) if you use Julia 1.3 or later.
 Currently, Windows, Linux, macOS, and FreeBSD are now supported.
 
+Version compatibility
+---------------------
+
+| EzXML.jl | Julia        |
+|:--------:|:------------:|
+| 1.0      | 1.0 or later |
+| 1.1      | 1.3 or later |
+
 Usage
 -----