Try to fix test on 0.6

Author: ararslan

test/runtests.jl

@@ -1307,7 +1307,14 @@ end
 
 # 0.7.0-DEV.3585
 let buf = IOBuffer()
-    printstyled(IOContext(buf, :color=>true), "foo", color=:red)
+    if VERSION < v"0.7.0-DEV.3077"
+        col = Base.have_color
+        eval(Base, :(have_color = true))
+        printstyled(buf, "foo", color=:red)
+        eval(Base, :(have_color = $col))
+    else
+        printstyled(IOContext(buf, :color=>true), "foo", color=:red)
+    end
     @test startswith(String(take!(buf)), Base.text_colors[:red])
 end