Fix closing and self-closing tags in templates

Void tags (e.g. <img>) couldn't have a closing tag (e.g. </img> is invalid). Non-void tags (e.g. <div>) couldn't be self closing (e.g. <div/> is invalid) and must be closed explicitly (e.g. with </div>). This CL fixes the tags which also prepares the templates for stricthtml which enforces it.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=168829028

java/google/registry/tools/soy/DomainCreate.soy

@@ -16,7 +16,7 @@
 /**
  * Create domain
  */
-{template .domaincreate}
+{template .domaincreate stricthtml="false"}
   {@param domain: string}
   {@param? period: string}
   {@param nameservers: list<string>}