List, set and delete a project's environment variables

## Usage

`circleci envvar <command> [flags]`

## General Commands

| Command | Description                        |
| ------- | ---------------------------------- |
| `list`  | List project environment variables |

## Targeted Commands

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

## Flags

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

## Examples

- List all environment variables for the current project: 
  `circleci envvar list`
- Set an environment variable: 
  `circleci envvar set MY_SECRET s3cr3t --project gh/myorg/myrepo`
- Delete an environment variable: 
  `circleci envvar delete MY_SECRET`

## 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.

Also available as: circleci project envvar `<command>`

