We preload to ensure as much memory as possible is reused from unicorn master
to various workers using copy-on-write (sidekiq, unicorn)
This migrates the preloading code into the Discourse module for easier
reuse and adds 3 notable preloading changes
1. We attempt to localize a string on each site, ensuring we warmup
the i18n
2. We preload all our templates (compiling .erb to class)
3. We warm-up our search tokenizer which uses cppjieba which is a large
memory consumer, this will only cause a warmup on CJK sites or sites with
the special site setting enabled.
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