Update binaries to e93206e

https://github.com/libgit2/libgit2/compare/90befde...e93206e
Add Clone() test leveraging authentication
Fix xml doc related warnings
Test -> CanResolveConflictsByRemovingFromTheIndex

We're not clearing the conflicts, we're resolving them.  The
difference is that removing from the index means that the items
get moved to the REUC.  "Clearing" or "removing" (in libgit2
terminology, anyway) means that they are removed without being
resolved (or going into the REUC).
Introduce Index.Conflicts.ResolvedConflicts
Introduce Repository.Index.Conflicts.Names
Introduce merge.ff configuration handling

When the provided FastForwardStrategy is FastForwardStrategy.Default,
honor the merge.ff configuration setting.  When merge.ff=only, enable
fast-forward only mode; when merge.ff=false, enable no-ff mode.
Remove conflicts in Index.Remove
Refactor Constants.PrivateRepoCredentials
Restore old Credentials API as Obsolete