Add initial support for Owon AC201 Thermostat [02]

[SwoopX]

• Add initial support for Owon AC201 Thermostat
• Introduce fan_control.cpp to accomodate AC fan control for thermostats
• Introduce RConfigFanMode to set AC fan mode
• Introduce RConfigSwingMode to set AC louvers position

[manup]

No errors just a few comments :)

[manup]

The code has no errors, but for consistency please stick to camelCase — ugly, but well that's Qt style :)
Also use QLatin1String for all static strings, since it as no extra cost, only the pointer and length is stored. QString("abcd") always results in extra allocations on the heap and utf-8 conversion, not dramatic but it piles up.

Since mode has only one value, else if prevents evaluating every statement.

    QString  modeSet = QLatin1String("fully closed");
    
    if      ( mode == 0x01 ) { modeSet = QLatin1String("fully closed"); }
    else if ( mode == 0x02 ) { modeSet = QLatin1String("fully open"); }
    else if ( mode == 0x03 ) { modeSet = QLatin1String("quarter open"); }
    else if ( mode == 0x04 ) { modeSet = QLatin1String("half open"); }
    else if ( mode == 0x05 ) { modeSet = QLatin1String("three quarters open"); }

[manup]

Just a note for the future: We don't have a coding style yet, but always use c++ named casts instead old C style casts.

static_cast<quint16>(attrId)

This might seam a bit superfluous at first. But soon the next generation code will get proper types for certain values like ZclAttributeId_t, EndpointId_t, etc to prevent common mistakes.

The named casts help the compiler to figure out invalid type conversions at compile time to prevent accidental errors.

For example:

ZclAttributeId_t attrId(0x0077);

stream << (quint8) attrId;              // programmer mistake won't be detected by compiler
stream << static_cast<quint8>(attrId);  // compile error no valid conversion from ZclAttributeId_t to quint8
stream << static_cast<quint16>(attrId); // ok
stream << attrId;                       // ok, because operator<< for QDataStream

So once we have the new types we only need to change the function signature:

addTaskFanControlReadWriteAttribute(TaskItem &task, uint8_t readOrWriteCmd, uint16_t attrId, uint8_t attrType, uint32_t attrValue, uint16_t mfrCode)

to

addTaskFanControlReadWriteAttribute(TaskItem &task, uint8_t readOrWriteCmd, ZclAttributeId_t attrId, ZclDatatypeId_t attrType, uint32_t attrValue, ZclManufacturerCode_t mfrCode)

If we already use C++ named casts we get a hole lot of error checking without needing to rewrite all those C style casts, searching for them is also quite hard/impossible.