Add smartcn_word and smartcn_sentence back for backwards compatibility

In f4d0d27 the deprecated `smartcn_sentence` tokenizer and deprecated `smartcn_word` token filter were removed as the new all in one `smartcn_tokenizer` should be used instead. However for those with pre-existing indices with mappings that reference the deprecated tokenizer and token filter this changes causes indexing and search errors.

This change preserves the `smartcn_sentence` tokenizer name and aliases it to the new `smartcn_tokenizer`. The change set also reintroduces a `smartcn_word` token filter that is a noop filter. The result of these changes should allow elasticsearch instances with the existing deprecated mappings to upgrade and take advantage of the new tokenizer in lucene.