Merge branch 'attr_encryped_no_db_connection' into 'master'

Don't require DB connection in AttrEncrypted.

See merge request !667

config/initializers/attr_encrypted_no_db_connection.rb

+module AttrEncrypted
+  module Adapters
+    module ActiveRecord
+      def attribute_instance_methods_as_symbols_with_no_db_connection
+        # Use with_connection so the connection doesn't stay pinned to the thread.
+        connected = ::ActiveRecord::Base.connection_pool.with_connection(&:active?) rescue false
+        
+        if connected
+          # Call version from AttrEncrypted::Adapters::ActiveRecord
+          attribute_instance_methods_as_symbols_without_no_db_connection
+        else
+          # Call version from AttrEncrypted, i.e., `super` with regards to AttrEncrypted::Adapters::ActiveRecord
+          AttrEncrypted.instance_method(:attribute_instance_methods_as_symbols).bind(self).call
+        end
+      end
+
+      alias_method_chain :attribute_instance_methods_as_symbols, :no_db_connection
+    end
+  end
+end