Don't set last active timestamp automatically

Ignore-this: 1615dd1f7401ba10625e9ea614d68144

darcs-hash:20131127142759-56b4d-4e6d8c45c6252ccec1ca723285344d4daa0a619b
Always pass copies of stream lists in notifications

Ignore-this: 54378f5c90e6dc612086e35cc6a75fc2

darcs-hash:20131205084723-56b4d-66e52a35ad8d43fb609d0de79f8cd80d2e1168f4
Avoid making unnecessary copies

Ignore-this: d8887c9c726c760cb3876d69853b91b4

darcs-hash:20131205085431-56b4d-071b5f6ea86e48da693d9e4d3478cb29c8ad27c9