fix 'convert' with single commit repositories
The attached patch passes the three 'convert' testcases, and also is
able to successfully convert the git.git repository.
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Should display 'First commit message'
description:
First commit message
=======================
Should display 'Second commit message'
description:
Second commit message
=======================
Should display 'Third commit message\n This is the 3rd log message'
description:
Third commit message
This is the 3rd log message
=======================
Should display 'Fifth commit message\n This is the 5th log message'
description:
Fifth commit message