Add simple app functionality

This commit enables anyone to create a app and add 3 types of data
sources:

* pdf file
* youtube video
* website

It exposes a function called query which first gets similar docs from
vector db and then passes it to LLM to get the final answer.

embedchain/loaders/website.py

@@ -0,0 +1,30 @@
+import requests
+
+from bs4 import BeautifulSoup
+
+from embedchain.utils import clean_string
+
+
+class WebsiteLoader:
+
+    def load_data(self, url):
+        response = requests.get(url)
+        data = response.content
+        soup = BeautifulSoup(data, 'html.parser')
+        for tag in soup([
+            "nav", "aside", "form", "header",
+            "noscript", "svg", "canvas",
+            "footer", "script", "style"
+        ]):
+            tag.string = " "
+        output = []
+        content = soup.get_text()
+        content = clean_string(content)
+        meta_data = {
+            "url": url,
+        }
+        output.append({
+            "content": content,
+            "meta_data": meta_data,
+        })
+        return output