chore: alecthomas/template -> text/template

[akojo]

Describe the PR

Since alecthomas/template is based on a severely outdated version (1.4)
of Go standard library, replace it with text/template in generated code.

Update example docs to match the change.

Additional context

Current code doesn't seem to be using newline elision anywhere. In case
that would be needed, text/template has supported it since Go 1.6.

[codecov]

Codecov Report

Merging #891 (2f3b7db) into master (e7c5cda) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #891   +/-   ##
=======================================
  Coverage   84.83%   84.83%           
=======================================
  Files           8        8           
  Lines        1649     1649           
=======================================
  Hits         1399     1399           
  Misses        145      145           
  Partials      105      105           

Impacted Files	Coverage Δ
gen/gen.go	95.27% <ø> (ø)

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[ubogdan]

LGTM

[ubogdan]

@easonlin404 any input here?

[easonlin404]

LGTM I think text/template standard lib is more suitable if we want to get support and more stable.

[ubogdan]

@akojo Thanks for your contributions.

[olliefr]

Closes issue #754, just saying 🙃

[olliefr]

@ubogdan hey, sorry to trouble you but do you guys have any time scale for the next version-tagged release, pretty please? 🙏 I'm very anxious to get rid of the alecthomas/template dependency in our project 😅

[christian-kreuzberger-dtx]

Same here!

[shepherdjerred]

Thanks for removing this dependency! This made our lives a bit easier :)

[ubogdan]

You're wellcome.