add readme

README.md

@@ -0,0 +1,33 @@
+## Coverage merger
+
+Library/tool to merge two or more coverage files into single one.
+
+Supported formats:
+* clover
+* junit (todo)
+
+### Install
+
+// todo
+
+### Usage
+
+It's cli-app with single access point:
+
+```shell
+./merger
+```
+
+```text
+clover-merger, version 1.0.0
+
+Commands:
+*
+  clover    Merge clover coverage files into single one
+
+Run `<command> --help` for specific help
+```
+
+### Additional info
+
+Clover merge logic based on [d0x2f/CloverMerge](https://github.com/d0x2f/CloverMerge).