Have a separate folder for each component type under integrations

[bilgeyucel]

Is your feature request related to a problem? Please describe.
As a user, I'm familiar with the convention at haystack repository and having the same convention here would make it easy for me to navigate.

Describe the solution you'd like
Create a /generators folder under cohere_haystack integration folder.
The same can apply to jina_haystack and unstructured. This way, we can be more open to new components coming from the same providers

Describe alternatives you've considered
We can leave it as it is.

Additional context
N/A

Tasks

Preview Give feedback

1. amazon_bedrock: mount integration under haystack_integrations.* #195
   P1 integration:amazon-bedrock +2
   
2. astra: mount integration under haystack_integrations.* #196
   P1 integration:astra +2
   
3. cohere: mount integration under haystack_integrations.* #197
   P1 integration:cohere +2
   
4. elasticsearch: mount integration under haystack_integrations.* #198
   P1 integration:elasticsearch +2
   
5. google_ai: mount integration under haystack_integrations.* #199
   P1 integration:google-ai +2
   
6. google_vertex: mount integration under haystack_integrations.* #200
   P1 integration:google-vertex +2
   
7. gradient: mount integration under haystack_integrations.* #201
   1 of 1
   P1 integration:gradient +2
   
8. instructor_embedders: mount integration under haystack_integrations.* #202
   P1 integration:instructor-embedders +2
   
9. jina: mount integration under haystack_integrations.* #203
   P1 integration:jina +2
   
10. llama_cpp: mount integration under haystack_integrations.* #210
    P1 integration:llama_cpp +2
    
11. ollama: mount integration under haystack_integrations.* #209
    P1 integration:ollama +2
    
12. opensearch: mount integration under haystack_integrations.* #208
    1 of 1
    P1 integration:opensearch +2
    
13. pinecone: mount integration under haystack_integrations.* #207
    P1 integration:pinecone +2
    
14. qdrant: mount integration under haystack_integrations.* #206
    P1 integration:qdrant +2
    
15. unstructured: mount integration under haystack_integrations.* #205
    P1 integration:unstructured-fileconverter +2
    
16. weaviate: mount integration under haystack_integrations.* #204
    P1 integration:weaviate +2
    
17. chroma: mount integration under haystack_integrations.* #213
    integration:chroma +1
    

[masci]

We're going to uniform the import path of all the integrations under the namespace haystack_integrations.*.

For example, this means that a document store FooDocumentStore shipped with the integration baz-haystack will be imported like this:

from haystack_integrations.document_stores.baz import FooDocumentStore

Similarly, a generator AwesomeGenerator shipped with the integration foo-haystack will be imported like this:

from haystack_integrations.components.generators.foo import AwesomeGenerator