firely base fhir client

BaseFhirClient.cs

using Hl7.Fhir.Model;
...

namespace Hl7.Fhir.Rest
{
    public abstract partial class BaseFhirClient : IDisposable
    {
        ...

        public Task<Resource> GetAsync(string url) 
        { ... }

        public Task<TResource> CreateAsync<TResource>(TResource resource) 
            where TResource : Resource
        { ... }
        
        public Task<TResource> UpdateAsync<TResource>(TResource resource, bool versionAware = false) 
            where TResource : Resource
        { ... }
...}
}