Fix TransportException when reading bundle

Fix TransportException when reading bundle

When reading a bundle file, commit messages who's oneline format is
longer than 982 characters caused JGit to treat subsequent text in
the commit as a SHA, then throw a TransportException because it's
not a valid SHA.

Now the readLine method will read all the way to the end of the
line, not just the first 1024 characters of it.

Change-Id: If15b491aa9a1e4fd9b8bbed2dd9e6be47a64ccb7
Signed-off-by: Chris Gavin <chris@chrisgavin.me>