Environment: Mark hasKey(...) method as const

Change-Id: I8f355e6ead9136741af199d08935a0f3e7446110
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>
LocalRunControl: Fix wrong "exited with error code -1" output

Task-number: QTCREATORBUG-8337
Change-Id: I585b6330e6aa18891ebf0171bf6c8813761943f1
Reviewed-by: Robert Loehning <robert.loehning@digia.com>