Move falco formats code out of engine

This isn't used by the engine itself anymore, now that it uses
factories to provide formatters.

This is in preparation for other changes to make the falco engine
hot-swappable while running.

Signed-off-by: Mark Stemm <mark.stemm@gmail.com>

userspace/engine/CMakeLists.txt

@@ -18,8 +18,7 @@ set(FALCO_ENGINE_SOURCE_FILES
     falco_engine.cpp
     falco_utils.cpp
     json_evt.cpp
-    ruleset.cpp
-    formats.cpp)
+    ruleset.cpp)
 
 add_library(falco_engine STATIC ${FALCO_ENGINE_SOURCE_FILES})
 add_dependencies(falco_engine njson lyaml lpeg string-view-lite)

userspace/engine/falco_engine.cpp

@@ -26,8 +26,6 @@ limitations under the License.
 #include "falco_utils.h"
 #include "falco_engine_version.h"
 
-#include "formats.h"
-
 extern "C" {
 #include "lpeg.h"
 #include "lyaml.h"

userspace/falco/CMakeLists.txt

@@ -25,6 +25,7 @@ set(
   event_drops.cpp
   statsfilewriter.cpp
   falco.cpp
+  formats.cpp
 )
 
 set(