Write WP-CLI instead of wpcli in project description

As used in the official site wp-cli.org, WP-CLI should be written WP-CLI (and not wpcli)

created branch 12-write-wp-cli-instead-of-wpcli-in-project-description

mentioned in merge request !8 (closed)

mentioned in commit ed6b73f9

mentioned in merge request !9 (merged)

changed milestone to %1.0.2

closed via commit ed6b73f9

closed via merge request !9 (merged)

mentioned in commit 53f911f9