more plugins for coveriti, fixed gccgo
improved gccgo plugin
moved go to broken plugins
try to address EAGAIn body read problem
metrics: add missing exit on error path

Fixed null pointer dereference.

Reported by Coverity as CID #1127337
plugins/servlet: Check uwsgi_jvm_exception return value

Reported vy Coverity as CID #1125169.
plugins/xslt: fix memory leak

Reported by Coverity as CID #1125168
plugins/xslt: fail early if content_type is null

Fixes null pointer dereference.

Reported by Coverity as CID #1125161
fixed metric bug discovered by coverity
core: fix memory leak

Reported by Coverity as CID #1100819
plugins/corerouter: fix memory leak

While at it reindent the code

Reported by Coverity as CID #1100818.
core: fix memory leak

Reported by Coverity as CID #1100813.
core/logging: if we cannot reopen the log exit

This fixes passing negative fds to write and lseek.

Reported by Coverity as CID #1100807.
first hardcore commit for supporting gccgo coroutines
avoid GC to destroy go request env
remove useless gccgo code
fixed async queue full condition in goroutine mode
removed matheval flag, added generic matheval plugin and startin 1.9.20 development cycle
removed snapshotting old feature
added simple math routing actions