drop the 'better_plugins' TODO from todo.md
drop the 'better_plugins' TODO from todo.md

We didn't do exactly what was described here but we did achieve the goals with the new SoySourceFunction hierarchy and configuration apis

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=238674130

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