Add support for namespaced attributes in DynamicAttributes

Add support for namespaced attributes in DynamicAttribute with a recursive approach (a DynamicAttribute can have an attribute of type DynamicAttribute). Usage example (both syntaxes are correct):

attrs.get_attr("mem.data.b")
attrs.get_attr("mem").get_attr("data").get_attr("b")

This is a preliminary work in order to introduce a general mechanism for specifiyng backend and export attributes.

• Needs more tests in Python.
• Use snake convention for all attributes naming in C++ and Python.
• Solve #142 (closed)

include/aidge/utils/DynamicAttributes.hpp

@@ -144,17 +144,15 @@ public:
     void delAttr(const std::string& name) {
         const auto dot = name.find('.');
         if (dot == name.npos) {
-            AIDGE_ASSERT(isPascalCase(name), "Aidge standard requires PascalCase for C++ Attributes for \"{}\".", name);
-            mAttrs.erase(name);
+            mAttrs.erase((isSnakeCase(name)) ? snakeToPascal(name) : name);
 #ifdef PYBIND
-            mAttrsPy.erase(pascalToSnake(name));
+            mAttrsPy.erase((isPascalCase(name)) ? pascalToSnake(name) : name);
 #endif
         }
         else {
             const auto ns = name.substr(0, dot);
-            AIDGE_ASSERT(isPascalCase(ns), "Aidge standard requires PascalCase for C++ Attributes namespace for \"{}\".", ns);
             const auto nsName = name.substr(dot + 1);
-            future_std::any_cast<DynamicAttributes&>(mAttrs.at(ns)).delAttr(nsName);
+            future_std::any_cast<DynamicAttributes&>(mAttrs.at((isSnakeCase(ns)) ? snakeToPascal(ns) : ns)).delAttr(nsName);
         }
     }