First version of Scrapling full documentation

docs/development/automatch_storage_system.md

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+Scrapling uses SQLite by default, but this tutorial covers writing your storage system to store element properties there for auto-matching.
+
+You might want to use FireBase, for example, and share the database between multiple spiders on different machines. It's a great idea to use an online database like that because the spiders will share with each other.
+
+So first, to make your storage class work, it must do the big 3:
+
+1. Inherit from the abstract class `scrapling.core.storage_adaptors.StorageSystemMixin` and accept a string argument, which will be the `url` argument to maintain the library logic.
+2. Use the decorator `functools.lru_cache` on top of the class to follow the Singleton design pattern as other classes.
+3. Implement methods `save` and `retrieve`, as you see from the type hints:
+    - The method `save` returns nothing and will get two arguments from the library
+        * The first one is of type `lxml.html.HtmlElement`, which is the element itself. It must be converted to a dictionary using the function `element_to_dict` in submodule `scrapling.core.utils._StorageTools` to keep the same format and save it to your database as you wish.
+        * The second one is a string, the identifier used for retrieval. The combination result of this identifier and the `url` argument from initialization must be unique for each row, or the auto-match will be messed up.
+    - The method `retrieve` takes a string, which is the identifier; using it with the `url` passed on initialization, the element's dictionary is retrieved from the database and returned if it exists; otherwise, it returns `None`.
+
+> If the instructions weren't clear enough for you, you can check my implementation using SQLite3 in [storage_adaptors](https://github.com/D4Vinci/Scrapling/blob/main/scrapling/core/storage_adaptors.py) file
+
+If your class meets these criteria, the rest is easy. If you plan to use the library in a threaded application, ensure your class supports it. The default used class is thread-safe.
+
+Some helper functions are added to the abstract class if you want to use them. It's easier to see it for yourself in the [code](https://github.com/D4Vinci/Scrapling/blob/main/scrapling/core/storage_adaptors.py); it's heavily commented :)
+
+
+## Real-World Example: Redis Storage
+
+Here's a more practical example generated by AI using Redis:
+
+```python
+import redis
+import orjson
+from functools import lru_cache
+from scrapling.core.storage_adaptors import StorageSystemMixin
+from scrapling.core.utils import _StorageTools
+
+@lru_cache(None)
+class RedisStorage(StorageSystemMixin):
+    def __init__(self, host='localhost', port=6379, db=0, url=None):
+        super().__init__(url)
+        self.redis = redis.Redis(
+            host=host,
+            port=port,
+            db=db,
+            decode_responses=False
+        )
+        
+    def save(self, element, identifier: str) -> None:
+        # Convert element to dictionary
+        element_dict = _StorageTools.element_to_dict(element)
+        
+        # Create key
+        key = f"scrapling:{self._get_base_url()}:{identifier}"
+        
+        # Store as JSON
+        self.redis.set(
+            key,
+            orjson.dumps(element_dict)
+        )
+        
+    def retrieve(self, identifier: str) -> dict:
+        # Get data
+        key = f"scrapling:{self._get_base_url()}:{identifier}"
+        data = self.redis.get(key)
+        
+        # Parse JSON if exists
+        if data:
+            return orjson.loads(data)
+        return None
+```