List, set and delete a project's environment variables

## Usage

`circleci project envvar <command> [flags]`

## Available Commands

| Command  | Description                           |
| -------- | ------------------------------------- |
| `delete` | Delete a project environment variable |
| `list`   | List project environment variables    |
| `set`    | Set a project environment variable    |

## Flags

Global flags: `-c, --config`, `--debug`, `--no-color`, `-q, --quiet` — see `circleci --help`.

## Details

List, set, and delete environment variables for a CircleCI project.

Environment variable values are masked in list output (shown as "xxxx").
The full value is never retrievable after it has been set.

For quick access, use the top-level alias:
  circleci envvar list --project gh/org/repo

