Remove Category from exports

Updated tests to use Unicode.Category

Author: ScottPJones

base/exports.jl

@@ -22,7 +22,6 @@ export
     Serializer,
     Docs,
     Markdown,
-    Category,
     Unicode,
 
 # Types

test/unicode/properties.jl

@@ -143,9 +143,9 @@ end
 
 # check handling of CN category constants
 let c_ll = 'β', c_cn = '\u038B'
-    @test charprop(Category.Code, c_ll) == Category.Ll
+    @test charprop(Unicode.Category.Code, c_ll) == Unicode.Category.Ll
     # check codepoint with category code CN
-    @test charprop(Category.Code, c_cn) == Category.Cn
+    @test charprop(Unicode.Category.Code, c_cn) == Unicode.Category.Cn
 end
 
 # Make sure fastplus is called for coverage