FIX: Add a special X-Accel-Buffering: no header for transparent replays that are very large (>100M).
For now this setting is fixed/enabled by default, may add additional configuration later.
Useful setting but a generally rare use case (very large files in wayback)
CDX-Server: cleanup of property names, add generic getCdx() function that doesn't rely on Spring
Seperate auth checking into generic AuthChecker and WaybackAuthChecker to allow customization of url access checking