Reenable net.ipv4.tcp_tw_reuse=1
Reenable net.ipv4.tcp_tw_reuse=1

gearmand relied on net.ipv4.tcp_tw_reuse being set to 1 (enabled in
b1da9b5). Apparently, PgBouncer runs out of TIME_WAIT sockets too, so
when trying to connect we would sometimes get:

Unable to connect to DSN dbi:Pg:dbname=mediacloud;host=mcdb2-private;port=6432;: DBI error: could not connect to server: Cannot assign requested address
    Is the server running on host "mcdb2-private" (10.200.200.11) and accepting
    TCP/IP connections on port 6432? at /home/mediacloud/mediacloud/local/bin/../../lib/MediaWords/DB/Handler.pm line 86.

(See http://dba.stackexchange.com/a/59709 for more details.)

berkmancenter/mediacloud,berkmancenter/mediacloud,berkmancenter/mediacloud,berkmancenter/mediacloud,berkmancenter/mediacloud