Add cEMV support feature

[skalexch]

Describe the problem

Since we adopted cemv_support, we should include it as a feature.

Fares -> cEMV Support

Proposed solution

If the field cemv_support exists in at least one entry inagency.txt or in routes.txt, then the feature exists.

Alternatives you've considered

No response

Additional context - (resolved - read the proposed solution for implementation)

@emmambd does the name "cEMV support" imply that the agency/routes of the feed automatically support cEMV? Theoretically, we can have cEMV_support have a value of 2 (cEMV not supported) everywhere or even have a value of 0 (no info on cEMV support). For example, if the value is 0, the field exists but we have no information on whether cEMV is supported or not.

Maybe another name would be better? @Sergiodero

[emmambd]

@skalexch @Sergiodero Do riders see something visible if cEMV_support is 0 or 2 in a trip planning app? If not, I'd suggest we refine the logic so there have to be at least one instance of cEMV_support =1 in agency.txt or routes.txt.

[skalexch]

@emmambd the "supports contactless payment" message should only appear if cEMV_support =1, since it means that the route/agency supports it.

[skalexch]

@emmambd the logic behind the features is that: If the value exists (regardless of the value), then the agency is actively understanding and implementing the feature.
This has nothing to do with what the rider would see. It is the same for other features like BIKE ALLOWED.
I spoke with @Sergiodero and it makes sense to leave as is for the sake of consistency. There might be a conversation regarding the interpretation of the names of features at some point maybe.

[emmambd]

@skalexch Clear! We'll proceed with the logic as defined originally then.

[qcdyx]

• add contactless EMV support feature
• update features.md doc