1/Update setup.py to support following modes:

- default (most frequent mode)
- torch
- transformers
- all
2/ Update Docker file
3/ Update documentation as well.

crawl4ai/extraction_strategy.py

@@ -10,7 +10,7 @@ from functools import partial
 from .model_loader import *
 import math
 
-import numpy as np
+
 class ExtractionStrategy(ABC):
     """
     Abstract base class for all extraction strategies.
@@ -219,6 +219,8 @@ class CosineStrategy(ExtractionStrategy):
         """
         super().__init__()
         
+        import numpy as np
+        
         self.semantic_filter = semantic_filter
         self.word_count_threshold = word_count_threshold
         self.max_dist = max_dist