std.format: Add %g (step 3): Add template parameter to printFloatE/F.

[berni44]

Another followup on #7810. Can be merged independently of #7815.

Precision is already adjusted in printFloatG so it is not necessary to repeat this in printFloatE/F.

See #7804 for the background.

[dlang-bot]

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[RazvanN7]

I think it would be useful to include in the description of these PRs the initial (closed) PR so that other reviewers have a chance to understand the broader picture. I will merge this for now, but anyone else reviewing this will not understand what the point is.

[berni44]

I think it would be useful to include in the description of these PRs the initial (closed) PR so that other reviewers have a change to understand the broader picture. I will merge this for now, but anyone else reviewing this will not understand what the point is.

Added the link to the initial comment. Thanks for pointing this out.