#17 Core dump during largge binary table dumps

[Craig Labovitz]

In dump_binary_bgp_view we only checked for
if ((end - cp) < 500)

before filling in all the rt_head information in the buffer. Turns out that with large numbers of peers, 500 bytes was woefully inadequate and we were overfilling the buffer. As a temporary fix, I upped the check to 1500. The correct solution is to actually check for overflow during the rt_head route iteration process.