Add more examples to Soy line joining docs + try to help clarify how it differs from straight HTML.
Add more examples to Soy line joining docs + try to help clarify how it differs from straight HTML.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=326119957

google/closure-templates,google/closure-templates,yext/closure-templates,google/closure-templates,google/closure-templates,google/closure-templates,yext/closure-templates,yext/closure-templates,yext/closure-templates