Created OTPService.ValidateHotp (markdown)

OTPService.ValidateHotp.md

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+Namespace: `SimpleOTP`
+
+Assembly: `SimpleOTP.dll`
+
+Validates provided HOTP code with provided parameters.
+```csharp
+public static bool ValidateHotp(int otp, ref OTPConfiguration target, int toleranceSpan, bool resyncCounter);
+```
+### Parameters
+`otp` `Int32`
+
+HOTP code to validate.
+
+`target` [OTPConfiguration](https://github.com/XFox111/SimpleOTP/wiki/OTPConfiguration)
+
+OTP configuration for check codes generation.
+
+`toleranceSpan` `Int32`
+
+Counter span from which OTP codes remain valid.
+
+`resyncCounter` `Boolean`
+
+Defines whether method should resync <see `OTPConfiguration.Counter` of the `target` or not after successful validation.
+### Returns
+`True` if code is valid, `False` if it isn't.
+
+### Exceptions
+[ArgumentException](https://docs.microsoft.com/en-us/dotnet/api/system.ArgumentException?view=net-5.0)
+
+`target.Type` is `OTPType.TOTP`
+
+[NullReferenceException](https://docs.microsoft.com/en-us/dotnet/api/system.nullreferenceexception?view=net-5.0)
+
+`target` is `null`
+### Examples
+See `OTPService` usage examples on [Code generation/validation](https://github.com/XFox111/SimpleOTP/wiki/Code-generation-or-validation)
+### Remarks
+Use this method only with HOTP codes.