Add exposure detection for README.md files (#4220)

* Add exposure detection for README.md files

* misc updates

Co-authored-by: sandeep <sandeep@projectdiscovery.io>

exposures/files/readme-md.yaml

@@ -0,0 +1,34 @@
+id: readme-md
+
+info:
+  name: README.md file disclosure
+  author: ambassify
+  severity: info
+  description: Internal documentation file often used in projects which can contain sensitive information.
+  metadata:
+    shodan-query: html:"README.MD"
+  tags: exposure,markdown
+
+requests:
+  - method: GET
+    path:
+      - "{{BaseURL}}/README.md"
+
+    matchers-condition: and
+    matchers:
+      - type: word
+        words:
+          - "#"
+          - "##"
+        condition: or
+
+      - type: word
+        part: header
+        words:
+          - "text/markdown"
+          - "text/plain"
+        condition: or
+
+      - type: status
+        status:
+          - 200