Add description and CLI arguments to repocloner README
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-Description goes here
+The FASTEN RepoCloner plugin is a tool for cloning repositories into the file system. It can be used both as a standalone plugin and as a part of the FASTEN Server.
## Arguments
-CLI arguments go here
+- `-h` `--help` Show this help message and exit.
+- `-f` `--file` Path to JSON file which contains groupId (repository owner), artifactId (repository name) and repository URL.
+- `-d` `--base-dir` Path to base directory where repository hierarchy will be created
## Usage
#### Some example
```shell script
-man example
+-f repo_urls/url.json -d data/repositories
```
