Removing LangChain and Rebuilding Executor (#1322)

* rebuilding executor

* removing langchain

* Making all tests good

* fixing types and adding ability for nor using system prompts

* improving types

* pleasing the types gods

* pleasing the types gods

* fixing parser, tools and executor

* making sure all tests pass

* final pass

* fixing type

* Updating Docs

* preparing to cut new version

src/crewai/utilities/printer.py

@@ -1,5 +1,8 @@
+from typing import Optional
+
+
 class Printer:
-    def print(self, content: str, color: str):
+    def print(self, content: str, color: Optional[str] = None):
         if color == "purple":
             self._print_purple(content)
         elif color == "red":