Update README.md

Author: jmservera

README.md

@@ -1,2 +1,18 @@
-# pptx-to-pdf
-A custom action to convert pptx files into pdf
+# Libreoffice cli action
+
+This action runs any command inside the libreoffice base image
+
+## Inputs
+
+## `command`
+
+**Required** The command line to run. Default `libreoffice --headless --invisible --version`.
+
+## Usage
+
+```yaml
+uses: actions/libreoffice-action@v1
+with:
+  # Required, the command to run
+  command: libreoffice --headless --invisible --convert-to pdf 'originalfile.pptx' --outdir 'output'
+```