tags: Add one or two template functions

[metal0]

adds like three missing template fns and documents some other ones that were missing from the docs

todo:

• alias trim_text => get_snowflake
• convert number types on convert_base to string
• reconsider how to specify available template function based on plugin type in the docs (currently adds (<plugin>)

[metal0]

HTTP 429 too many template functions :(