Added README and .gitattributes to help ppl

Author: szelpe

.gitattributes

@@ -0,0 +1 @@
+*.sh text eol=lf

README.md

@@ -0,0 +1,21 @@
+# Markdown tools
+
+## Build the image
+
+```bash
+docker build -t greenfox/markdown-tools:latest .
+```
+
+## Push to Docker Hub
+
+Use the `foxyfox` DockerHub user to add yourself to the greenfox organization.
+
+```bash
+docker login
+```
+
+Hopefully you'll get Login Succeeded.
+
+```bash
+docker push greenfox/markdown-tools:latest
+```