Added documentation for 'disable after cease'

	disable the instance automatically and wait for an administrator to fix

	the problem manually. Default: off.

        <tag><label id="bgp-disable-after-cease">disable after cease <m/switch/|<m/set-of-flags/</tag>

        When a Cease notification is received, disable the instance

        automatically and wait for an administrator to fix the problem manually.

        When used with <m/switch/ argument, it means handle every Cease subtype

        with the exception of <cf/connection collision/. Default: off.

        The <m/set-of-flags/ allows to narrow down relevant Cease subtypes. The

        syntax is <cf>{<m/flag/ [, <m/.../] }</cf>, where flags are: <cf/cease/,

        <cf/prefix limit hit/, <cf/administrative shutdown/,

        <cf/peer deconfigured/, <cf/administrative reset/,

        <cf/connection rejected/, <cf/configuration change/,

        <cf/connection collision/, <cf/out of resources/.

	<tag><label id="bgp-hold-time">hold time <m/number/</tag>

	Time in seconds to wait for a Keepalive message from the other side

	before considering the connection stale. Default: depends on agreement