📝 Add Path params and numeric validators docs

docs/tutorial/path-params-numeric-validations.md

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+The same way you can declare more validations and metadata for query parameters with `Query`, you can declare the same type of validations and metadata for path parameters with `Path`.
+
+## Import Path
+
+First, import `Path` from `fastapi`:
+
+```Python hl_lines="1"
+{!./tutorial/src/path-params-numeric-validations/tutorial001.py!}
+```
+
+## Declare metadata
+
+You can declare all the same parameters as for `Query`.
+
+For example, to declare a `title` metadata value for the path parameter `item_id` you can type:
+
+```Python hl_lines="8"
+{!./tutorial/src/path-params-numeric-validations/tutorial001.py!}
+```
+
+!!! note
+    A path parameter is always required as it has to be part of the path.
+    
+    So, you should declare it with `...` to mark it as required.
+
+    Nevertheless, even if you declared it with `None` or set a default value, it would not affect anything, it would still be always required.
+
+## Order the parameters as you need
+
+Let's say that you want to declare the query parameter `q` as a required `str`.
+
+And you don't need to declare anything else for that parameter, so you don't really need to use `Query`.
+
+But you still need to use `Path` for the `item_id` path parameter.
+
+Python will complain if you put a value with a "default" before a value that doesn't have a "default".
+
+But you can re-order them, and have the value without a default (the query parameter `q`) first.
+
+It doesn't matter for **FastAPI**. It will detect the parameters by their names, types and default declarations (`Query`, `Path`, etc), it doesn't care about the order.
+
+So, you can declare your function as:
+
+```Python hl_lines="8"
+{!./tutorial/src/path-params-numeric-validations/tutorial002.py!}
+```
+
+## Order the parameters as you need, tricks
+
+If you want to declare the `q` query parameter without a `Query` nor any default value, and the path parameter `item_id` using `Path`, and have them in a different order, Python has a little special syntax for that.
+
+Pass `*`, as the first parameter of the function.
+
+Python won't do anything with that `*`, but it will know that all the following parameters should be called as keyword arguments (key-value pairs), also known as <abbr title="From: K-ey W-ord Arg-uments"><code>kwargs</code></abbr>. Even if they don't have a default value.
+
+```Python hl_lines="8"
+{!./tutorial/src/path-params-numeric-validations/tutorial003.py!}
+```
+
+## Number validations: greater than or equal
+
+With `Query` and `Path` (and other's you'll see later) you can declare string constraints, but also number constraints.
+
+Here, with `ge=1`, `item_id` will need to be an integer number "`g`reater than or `e`qual" to `1`.
+
+```Python hl_lines="8"
+{!./tutorial/src/path-params-numeric-validations/tutorial004.py!}
+```
+## Number validations: greater than and less than or equal
+
+The same applies for:
+
+* `gt`: `g`reater `t`han
+* `le`: `l`ess than or `e`qual
+
+```Python hl_lines="9"
+{!./tutorial/src/path-params-numeric-validations/tutorial005.py!}
+```
+
+## Number validations: floats, greater than and less than
+
+Number validations also work for `float` values.
+
+Here's where it becomes important to be able to declare <abbr title="greater than"><code>gt</code></abbr> and not just <abbr title="greater than or equal"><code>ge</code></abbr>. As with it you can require, for example, that a value must be greater than `0`, even if it is less than `1`.
+
+So, `0.5` would be a valid value. But `0.0` or `0` would not.
+
+And the same for <abbr title="less than"><code>lt</code></abbr>.
+
+```Python hl_lines="11"
+{!./tutorial/src/path-params-numeric-validations/tutorial006.py!}
+```
+
+## Recap
+
+With `Query`, `Path` (and others you haven't seen yet) you can declare [metadata and string validations (the previous chapter)](/tutorial/query-params-str-validations).
+
+And you can also declare numeric validations:
+
+* `gt`: `g`reater `t`han
+* `ge`: `g`reater than or `e`qual
+* `lt`: `l`ess `t`han
+* `le`: `l`ess than or `e`qual