Fallback describes the mechanism, while unspecified explains what the
user is thinking.

Use the previously created function to display a message when the arguments are not valid.

ticket 3095

An anonymous remote is not configured and cannot therefore have
configured refspecs. Remove the parameter which adds this from the
constructor.

This lets us see what the server (or libgit2 locally) is doing, rather
than having to stare at a non-moving screen.

Code restructured to better represent best practice when
using libgit2.

Added forgotten call to git_libgit2_shutdown() to the /examples/network/git2.c.