Modify change.md

Author: linev

changes.md

@@ -1,6 +1,6 @@
 # JSROOT changelog
 
-## Changes in master
+## Changes in 3.8
 1.  Let use HTML element pointer in JSROOT.draw function like:
        JSROOT.draw(document.getElementsByTagName("div")[0], obj, "hist");
    Normally unique identifier was used before, which is not required any longer.