* Fix(Core/Misc): Acore::StringFormat to fmt format

Fixes the issue that variables are not properly replaced.
Instead placeholders %s,%u and %i were shown in chat.

Closes issue #187

* Fix(Core/Misc): Acore::StringFormat to fmt format

Fixes the issue that variables are not properly replaced.
Instead placeholders %.2f and %.3f were shown in chat.

Closes issue #187

* Adjusted format for float placehodlers

Makes sure the original formatting for float
placeholders still fits

Closes issue #187