Add Schneider Electric’s UMAS detection support

[0xA50C1A1]

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Describe changes:

UMAS is a Modbus-based proprietary protocol (or extension?) from Schneider Electric, used in their PLCs. Huh, adding support for this turned out to be quite trivial, as SE reserved a special Modbus function code for UMAS.

[IvanNardi]

LGTM, just a small issue

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

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[IvanNardi]

@utoni [unrelated to this PR] could you take a look at the error when downloading the gambling sites list, please? The HTML page might be different now and we might need to update the sed command...

[IvanNardi]

Thanks!

[utoni]

@utoni [unrelated to this PR] could you take a look at the error when downloading the gambling sites list, please? The HTML page might be different now and we might need to update the sed command...

will do

[IvanNardi]

@utoni [unrelated to this PR] could you take a look at the error when downloading the gambling sites list, please? The HTML page might be different now and we might need to update the sed command...

will do

Thanks!