Quality of life

In this merge request I propose multiple changes which should improve the usage of the Python API of Aidge:

New Features:

• Add a set_attr method to StaticAttribute objects
• Add a set_attr method to DynamicAttribute objects
• Add magic method __set_attr__ & __get_attr__ to StaticAttribute

Allow the use of

dilation_dims = conv.DilationDims  # __get_attr__ example
conv.DilationDims = [2, 2]         # __set_attr__ example

• Add magic method __set_attr__ & __get_attr__ to DynamicAttribute
• Add **kwargs to GeneriOp ctor to declare more easily attributes:

Usage example

test_op = aidge_core.GenericOperator(
        "Test_generic",
        1,
        0,
        1,
        name="test_op",
        attribute_1=1,
        attribute_2=True,
        attribute_3=0.001
    )

• Allow Numpy->Tensor conversion with no available Backends (move TensorImpl backend_cpu to core)
• Allow to specify a Backend to choose for Numpy->Tensor conversion

include/aidge/utils/StaticAttributes.hpp

@@ -202,6 +202,22 @@ public:
     }
 
     #ifdef PYBIND
+    /**
+     * @brief Return a set of attributes defined.
+     * This method is used to automatically retrieve attributes in the documentation.
+     * This method is a duplicate of ``getAttrsName`` but static.
+     *
+     * @return std::set<std::string>
+     */
+    static std::set<std::string> staticGetAttrsName() {
+        std::set<std::string> attrsName;
+        for (std::size_t i = 0; i < size(EnumStrings<ATTRS_ENUM>::data); ++i) {
+            attrsName.insert(EnumStrings<ATTRS_ENUM>::data[i]);
+        }
+        return attrsName;
+    }
+
+
     py::object getAttrPy(const std::string& name) const override {
         for (std::size_t i = 0; i < size(EnumStrings<ATTRS_ENUM>::data); ++i) {
             if (name == EnumStrings<ATTRS_ENUM>::data[i]) {