Deploy command fails on non-git repos.

**Describe the bug**
Unfortunately, it seems like the mbed website allows non-git repos and the deploy command assumes that they are all git.

**To Reproduce**
Steps to reproduce the behavior:
1. Create a new project.
2. Add https://os.mbed.com/users/romilly/code/MCP23S17/#068b1e8909bb to a .lib file.
3. Run `mbedtools deploy`

**Expected behavior**
The repository is cloned into the current directory.

**Current behavior**
The command fails because this is a mericurial repository, not a git one.
```
Cloning into '#068b1e8909bb'...
fatal: https://os.mbed.com/users/romilly/code/MCP23S17/#068b1e8909bb/info/refs not valid: could not determine hash algorithm; is this a git repository?
```

### Solving the Problem

We need a way to tell what version control system a project is using and select the appropriate tool.
Or just wipe all these projects off the site, that works too :smiling_imp:

Start with the `mbedtools deploy` command and reproduce the failure using the MCP23S17 URL in the issue's `.lib` file. Trace how the command selects a repository tool, then verify that deployment supports the non-Git repository and clones it into the current directory.

Written by the indexing model from the issue text.