Drall verbosity must not interfere with Drush verbosity

[jigarius]

Motivation

• When running a drall command with -vvv, the -vvv gets passed to Drush.
• Drush output can get very verbose with -vvv and it makes it hard to read the Drall log messages.

Proposed solution

• Use something like --drall-verbose and --drall-debug to control Drall's verbosity.
• These options should not be forwarded to Drush commands.