🔇 Error message cleanup

[phatblat]

Cleanup of error messages.

• Removed some duplicate error messages
• All errors printed to stderr now
• Added --verbose flag to outdated command. Warnings about apps removed from the App Store will only be shown when flag provided.

❯ mas outdated
803453959 Slack (4.28.182 -> 4.28.184)
1055511498 Day One (7.16 -> 7.17)

❯ mas outdated --verbose
Warning: Identifier 883878097 not found in store. Was expected to identify Server.
Warning: Identifier 1125131804 not found in store. Was expected to identify Later.
Warning: Identifier 588726889 not found in store. Was expected to identify ReadKit.
Warning: Identifier 980258689 not found in store. Was expected to identify SSDReporter.
Warning: Identifier 927292435 not found in store. Was expected to identify iStat Mini.
Warning: Identifier 1381523962 not found in store. Was expected to identify Houseparty.
Warning: Identifier 1475897096 not found in store. Was expected to identify Jira.
Warning: Identifier 781577745 not found in store. Was expected to identify Dumper.
Warning: Identifier 924726344 not found in store. Was expected to identify Deliveries.
803453959 Slack (4.28.182 -> 4.28.184)
1055511498 Day One (7.16 -> 7.17)