TS-2145: Add metrics for log collation

Without accurate stats, we don't known whether the log is lost.
This patch is used to verify, such as:

1) At log client side, how many logs genterated from HttpSM, how many
   logs sent to LogServer.

2) At log server side, how many logs received from LogClient, how many
   logs written to LogServers's disk.

After apply this patch, we will get the following metrics for logging:
 a) Events of Log::error():
    proxy.process.log.event_log_error_ok
    proxy.process.log.event_log_error_skip
    proxy.process.log.event_log_error_aggr
    proxy.process.log.event_log_error_full
    proxy.process.log.event_log_error_fail

 b) Events for Log::access():
    proxy.process.log.event_log_access_ok
    proxy.process.log.event_log_access_skip
    proxy.process.log.event_log_access_aggr
    proxy.process.log.event_log_access_full
    proxy.process.log.event_log_access_fail

 c) Logging Data to/from network/disk:
    proxy.process.log.num_sent_to_network
    proxy.process.log.num_received_from_network
    proxy.process.log.num_flush_to_disk
    proxy.process.log.bytes_sent_to_network
    proxy.process.log.bytes_received_from_network
    proxy.process.log.bytes_flush_to_disk
    proxy.process.log.bytes_written_to_disk

 d) Mix:
    proxy.process.log.log_files_open
    proxy.process.log.log_files_space_used

BTW: Remove LOG_XXX stats macro according Leif's suggestion.

Signed-off-by: Yunkai Zhang <qiushu.zyk@taobao.com>
Doc: Add lifecycle hook documentation.
ci: toggle --enable-wccp correctly for different platforms
ci: move jenkins jobs to the jenkins subdirectory
TS-2163 Remove obsolete WDA and ACC alarms feature

This was done for an Inktomi specific customer plugin, and no longer applies
to the project. If we later decide it necessary, we should add new APIs which
let plugins register new alarms with the system for appropriate handling.

Reading the code, it looks to me like the Alarms code was intended to be
replaced as well, so this could be part of a code refactoring/replacement.
Added TS-2163
Moved the two 4.0.1 changes that we respun build for.
Fix git paths for the 4.0.x branch in Jenkins
Add debug builds for 3.2.x and 4.0.x in the CI
ci: reduce the number of job templates
ci: build experimental configuration options
Doc: Add transaction buffering control.