nsqd: add max_msg_timeout and msg_timeout to IDENTIFY response
nsqd: add client configurable output buffering

* add --max-output-buffer-size command line option
* add --max-output-buffer-timeout command line option
nsqd: re-organize command line flags
add tests
nsqadmin: only use the host portion for cookie domain
Merge pull request #213 from mreiferson/admin_cookie_213

nsqadmin: cookie domain contains port
Merge pull request #196 from mreiferson/flush_196

nsqd: client configurable output buffering
nsqd: mark diskqueue for syncing when corrupt
nsqd: move code out of diskqueue ioLoop into functions
nsqd: add --sync-timeout for time based diskqueue fsync
nsqd: cleanup diskqueue files when we recover from tail corruption
nsqd: dont open diskqueue writeFile with O_APPEND

O_APPEND causes every write to first seek to the end of the file.
In cases where data was written to the end of a file but uncommitted
to the metadata position (due to process crash, etc.) subsequent
writes would be performed at the wrong position (we already seek()
to the commited write position when opening a writeFile)
Merge pull request #214 from mreiferson/dq_meh_214

nsqd: diskqueue cleanup