[CI] Added drone config and fixed badge url in README

.drone.yml

@@ -0,0 +1,32 @@
+---
+kind: 'pipeline'
+name: 'build'
+type: 'kubernetes'
+
+steps:
+
+# build and publish
+- image: 'docker.io/plugins/docker'
+  name: 'publish'
+  pull: 'always'
+  settings:
+
+    # registery and repos
+    registry: 'cr.simoncor.net'
+    repo: 'cr.simoncor.net/siempie/roundcube'
+    mtu: '1440'
+
+    # build stuff
+    dockerfile: 'Dockerfile.linux.amd64'
+    daemon_off: 'false'
+
+    # authentication
+    username:
+      from_secret: 'docker_username'
+    password:
+      from_secret: 'docker_password'
+
+    # tags
+    tags:
+    - 'v1'
+    - 'latest'

README.md

@@ -1,5 +1,4 @@
-[![Build Status](https://ci.simoncor.net/api/badges/siempie/hugo-sws/status.svg)](https://ci.simoncor.net/siempie/hugo-sws)
-
+[![Build Status](https://ci.simoncor.net/api/badges/siempie/roundcube/status.svg)](https://ci.simoncor.net/siempie/roundcube)
 Simple container with Roundcube and plugins pre-installed.
 
 | package | version | link |