dyncfg v2 (#16702)

* split rrdfunctions streaming and progress

* simplified internal inline functions API

* split rrdfunctions inflight management

* split rrd functions exporters

* renames

* base dyncfg structure

* config pluginsd

* intercept dyncfg function calls

* loading and saving of dyncfg metadata and data

* save metadata and payload to a single file; added code to update the plugins with jobs and saved configs

* basic working unit test

* added payload to functions execution

* removed old dyncfg code that is not needed any more

* more cleanup

* cleanup sender for functions with payload

* dyncfg functions are not exposed as functions

* remaining work to avoid indexing the \0 terminating character in dictionary keys

* added back old dyncfg plugins.d commands as noop, to allow plugins continue working

* working api; working streaming;

* updated plugins.d documentation

* aclk and http api requests share the same header parsing logic

* added source type internal

* fixed crashes

* added god mode for tests

* fixes

* fixed messages

* save host machine guids to configs

* cleaner manipulation of supported commands

* the functions event loop for external plugins can now process dyncfg requests

* unified internal and external plugins dyncfg API

* Netdata serves schema requests from /etc/netdata/schema.d and /var/lib/netdata/conf.d/schema.d

* cleanup and various fixes; fixed bug in previous dyncfg implementation on streaming that was sending the paylod in a way that allowed other streaming commands to be multiplexed

* internals go to a separate header file

* fix duplicate ACLK requests sent by aclk queue mechanism

* use fstat instead of stat

* working api

* plugin actions renamed to create and delete; dyncfg files are removed only from user actions

* prevent deadlock by using the react callback

* fix for string_strndupz()

* better dyncfg unittests

* more tests at the unittests

* properly detect dyncfg functions

* hide config functions from the UI

* tree response improvements

* send the initial update with payload

* determine tty using stdout, not stderr

* changes to statuses, cleanup and the code to bring all business logic into interception

* do not crash when the status is empty

* functions now propagate the source of the requests to plugins

* avoid warning about unused functions

* in the count at items for attention, do not count the orphan entries

* save source into dyncfg

* make the list null terminated

* fixed invalid comparison

* prevent memory leak on duplicated headers; log x-forwarded-for

* more unit tests

* added dyncfg unittests into the default unittests

* more unit tests and fixes

* more unit tests and fixes

* fix dictionary unittests

* config functions require admin access

121 files changed, 6597 insertions, 6064 deletions

diff --git a/.codacy.yml b/.codacy.yml
index cebc95f819..bcbd297c31 100644
--- a/.codacy.yml
+++ b/.codacy.yml
@@ -21,5 +21,4 @@ exclude_paths:
   - web/server/h2o/libh2o/**
   - build/**
   - build_external/**
-  - libnetdata/dyn_conf/tests/**
   - packaging/**
diff --git a/CMakeLists.txt b/CMakeLists.txt
index f6f8c6bd91..640940bc83 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -144,7 +144,7 @@ if(NOT ${DISABLE_HARDENING})
         endif()
 
         if(NOT ${CMAKE_C_FLAGS} MATCHES "stack-clash-protection")
-                check_c_compiler_flag("-fstack-clash-protection", HAVE_STACK_CLASH_FLAG)
+                check_c_compiler_flag("-fstack-clash-protection" HAVE_STACK_CLASH_FLAG)
                 if(HAVE_STACK_CLASH_FLAG)
                         set(EXTRA_HARDENING_FLAGS "${EXTRA_HARDENING_FLAGS} -fstack-clash-protection")
                 endif()
@@ -641,8 +641,10 @@ set(LIBNETDATA_FILES
         libnetdata/http/http_access.h
         libnetdata/http/http_defs.c
         libnetdata/http/http_defs.h
-        libnetdata/dyn_conf/dyn_conf.c
-        libnetdata/dyn_conf/dyn_conf.h
+        libnetdata/http/content_type.c
+        libnetdata/http/content_type.h
+        libnetdata/config/dyncfg.c
+        libnetdata/config/dyncfg.h