changelog: refuse to add revisions with empty usernames
An empty username or a username with a "\n" will make the revision
text contain two "\n\n" sequences -> corrupt repository.
The problem is that changelog.read expects to find exactly one "\n\n"
separator and thus cannot unpack the revision.
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1c590d34bf61e2ea12c71738e5a746cd74586157 0.4e
7eca4cfa8aad5fce9a04f7d8acadcd0452e2f34e 0.4d
b4d0c3786ad3e47beacf8412157326a32b6d25a4 0.4c
f40273b0ad7b3a6d3012fd37736d0611f41ecf54 0.5
0a28dfe59f8fab54a5118c5be4f40da34a53cdb7 0.5b
12e0fdbc57a0be78f0e817fd1d170a3615cd35da 0.6
4ccf3de52989b14c3d84e1097f59e39a992e00bd 0.6b
eac9c8efcd9bd8244e72fb6821f769f450457a32 0.6c
979c049974485125e1f9357f6bbe9c1b548a64c3 0.7
3a56574f329a368d645853e0f9e09472aee62349 0.8
6a03cff2b0f5d30281e6addefe96b993582f2eac 0.8.1
35fb62a3a673d5322f6274a44ba6456e5e4b3b37 0.9
2be3001847cb18a23c403439d9e7d0ace30804e9 0.9.1
36a957364b1b89c150f2d0e60a99befe0ee08bd3 0.9.2
27230c29bfec36d5540fbe1c976810aefecfd1d2 0.9.3
fb4b6d5fe100b0886f8bc3d6731ec0e5ed5c4694 0.9.4
23889160905a1b09fffe1c07378e9fc1827606eb 0.9.5
bae2e9c838e90a393bae3973a7850280413e091a 1.0
d5cbbe2c49cee22a9fbeb9ea41daa0ac4e26b846 1.0.1
d2375bbee6d47e62ba8e415c86e83a465dc4dce9 1.0.2
2a67430f92f15ea5159c26b09ec4839a0c549a26 1.1
3773e510d433969e277b1863c317b674cbee2065 1.1.1
11a4eb81fb4f4742451591489e2797dc47903277 1.1.2
11efa41037e280d08cfb07c09ad485df30fb0ea8 1.2
02981000012e3adf40c4849bd7b3d5618f9ce82d 1.2.1