Remove lib folder from autoload path

- Load extensions explicitly

lib/gem_ext/builder.rb

@@ -0,0 +1,14 @@
+require 'builder'
+
+class Builder::XmlMarkup
+  def epp_head
+    self.instruct!
+    epp(
+      'xmlns' => 'https://epp.tld.ee/schema/epp-ee-1.0.xsd',
+      'xmlns:xsi' => 'http://www.w3.org/2001/XMLSchema-instance',
+      'xsi:schemaLocation' => 'lib/schemas/epp-ee-1.0.xsd'
+    ) do
+      yield
+    end
+  end
+end