snippets: add snippet for type function declaration

[programmer04]

Add snippet with name tyf for type function declaration:

type name func() // snippet to fill
type Example func(string, int) error // example of filled snippet

Rationale - they are already:

• tyi - snippet for a type interface
• tys - snippet for a struct declaration

the only one missing is a snippet for type function declaration. It is quite common in Go to declare and use function types, so this new snippet makes a programmer's life easier

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Message from Hyang-Ah Hana Kim:

Patch Set 4: Run-TryBot+1 Code-Review+1

(1 comment)

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Patch Set 4:

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Patch Set 4: TryBot-Result+1

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Message from Hyang-Ah Hana Kim:

Patch Set 4: Trust+1

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Message from Suzy Mueller:

Patch Set 4: Code-Review+2 Trust+1

(1 comment)

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This PR is being closed because golang.org/cl/275572 has been merged.