* Remove a lot of deferred functions in the request path.
There is an interesting benchmark at https://www.reddit.com/r/golang/comments/3h21nk/simple_micro_benchmark_to_measure_the_overhead_of/
It shows that defer actually adds quite a lot of overhead -- maybe 100ns
per call but we defer a *lot* of functions in the request path. So this
removes some of the ones in request handling, ha, barrier, router, and
physical cache.
One meta-note: nearly every metrics function is in a defer which means
every metrics call we add could add a non-trivial amount of time, e.g.
for every 10 extra metrics statements we add 1ms to a request. I don't
know how to solve this right now without doing what I did in some of
these cases and putting that call into a simple function call that then
goes before each return.
* Simplify barrier defer cleanup
* logbridge with hclog and identical output
* Initial search & replace
This compiles, but there is a fair amount of TODO
and commented out code, especially around the
plugin logclient/logserver code.
* strip logbridge
* fix majority of tests
* update logxi aliases
* WIP fixing tests
* more test fixes
* Update test to hclog
* Fix format
* Rename hclog -> log
* WIP making hclog and logxi love each other
* update logger_test.go
* clean up merged comments
* Replace RawLogger interface with a Logger
* Add some logger names
* Replace Trace with Debug
* update builtin logical logging patterns
* Fix build errors
* More log updates
* update log approach in command and builtin
* More log updates
* update helper, http, and logical directories
* Update loggers
* Log updates
* Update logging
* Update logging
* Update logging
* Update logging
* update logging in physical
* prefixing and lowercase
* Update logging
* Move phyisical logging name to server command
* Fix som tests
* address jims feedback so far
* incorporate brians feedback so far
* strip comments
* move vault.go to logging package
* update Debug to Trace
* Update go-plugin deps
* Update logging based on review comments
* Updates from review
* Unvendor logxi
* Remove null_logger.go
