Don't validate KeyLen and ExtLen
Don't validate KeyLen and ExtLen

This just slows us down, and it's not really ebucketmigrator's job to
validate the stream anyway; this was just for initial testing.

Change-Id: I509b06be876fe098ad0ded4ef74c9690b2164d5a
Reviewed-on: http://review.membase.org/5216
Reviewed-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>
Tested-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>

membase/ns_server,mschoch/ns_server,nimishzynga/ns_server,t3rm1n4l/ns_server,nimishzynga/ns_server,nimishzynga/ns_server,ceejatec/ns_server,mschoch/ns_server,pavel-blagodov/ns_server,t3rm1n4l/ns_server,mschoch/ns_server,vzasade/ns_server,ceejatec/ns_server,vzasade/ns_server,membase/ns_server,daverigby/ns_server,t3rm1n4l/ns_server,daverigby/ns_server,pavel-blagodov/ns_server,vzasade/ns_server,membase/ns_server,membase/ns_server,pavel-blagodov/ns_server,ceejatec/ns_server,t3rm1n4l/ns_server,nimishzynga/ns_server,pavel-blagodov/ns_server,vzasade/ns_server,t3rm1n4l/ns_server,daverigby/ns_server,nimishzynga/ns_server,mschoch/ns_server,ceejatec/ns_server,daverigby/ns_server,mschoch/ns_server,mschoch/ns_server,daverigby/ns_server,membase/ns_server,ceejatec/ns_server,nimishzynga/ns_server,ceejatec/ns_server,membase/ns_server