Add Support for Stash Backup Client

Currently when we are making the Backup at a daily basis with the Stash Backup Client and Bamboo is checking for changes it fails with an error message.

(com.atlassian.bamboo.repository.RepositoryException : java.lang.RuntimeException: com.atlassian.bamboo.plugins.stash.repository.StashRepositoryException: com.atlassian.bamboo.repository.RepositoryException: com.atlassian.bamboo.plugins.git.GitCommandException: command 'C:\Program Files (x86)\Git\bin\git.exe' ls-remote ssh://3448c6b2-afda-43af-8c22-ef3fd88fae08@127.0.0.1:60328/lk/sourcen.git failed with code 128. Working directory was [.]., stderr: [Warning: Permanently added '[127.0.0.1]:60328' (RSA) to the list of known hosts., Stash is currently unavailable:, - The system is unavailable while maintenance is being performed., - Stash is unavailable while it is being backed up, fatal: Could not read from remote repository., , Please make sure you have the correct access rights, and the repository exists.])

Bamboo should be so smart that if the Stash Backup Client is running it should not add a system error.