This patch:
- adds the description of the `fuel2 delete graph` command
to the corresponding sub-section of Fuel CLI section;
- adds steps on how to delete a deployment workflow
to the Manage workflows sub-section of the Maintain your
env section;
- changes the following parameters as preferable in
fuel2 CLI where applicable: '--env' to '-e',
'--type' to '-t', '--release' to '-r', '--plugin' to '-p',
'--all' to '-a', '--cluster' to 'c';
- renames 'graph' to 'workflow';
- fixes noticed typos.
Change-Id: I2e88436792d812ba60f5189c4a572d680ed0ae21
Closes-Bug: #1633773