Major plugin refactor and cleanup.

Switched to POCO library for unified platform/library interface.
Deprecated the external module API. It was creating more problems than solving.
Removed most built-in libraries in favor of system libraries for easier maintenance.
Cleaned and secured code with help from static analyzers.

vendor/POCO/build/config/AppleTV

@@ -0,0 +1,96 @@
+#
+# AppleTV
+#
+# Build settings for tvOS 9.0 and newer
+# 
+
+#
+# General Settings
+#
+# tvOS does not allow dynamic linking to user libraries
+#
+LINKMODE ?= STATIC
+
+#
+# If the SDK is defined use it
+# Otherwise find the latest version installed
+#
+# TVOS_SDK_VERSION = 9.0
+
+# if TVOS_SDK_VERSION_MIN is defined use that
+# Otherwise use the version found. 
+
+TVOS_SDK             ?= AppleTVOS
+TVOS_SDK_ROOT        ?= $(shell xcode-select -print-path)/Platforms/$(TVOS_SDK).platform/Developer/SDKs
+TVOS_SDK_ROOT_DIR     = $(TVOS_SDK_ROOT)/$(TVOS_SDK)
+TVOS_SDK_BASE         = $(shell ls -d $(TVOS_SDK_ROOT_DIR)$(TVOS_SDK_VERSION)*.sdk | tail -1)
+TVOS_SDK_VERSION_MIN ?= $(patsubst %.sdk,%,$(patsubst $(TVOS_SDK_ROOT_DIR)%,%,$(TVOS_SDK_BASE)))
+
+POCO_TARGET_OSNAME     ?= $(TVOS_SDK)
+POCO_TARGET_OSARCH     ?= arm64
+TOOL_PREFIX            ?= $(shell xcode-select -print-path)/Platforms/$(TVOS_SDK).platform/Developer/usr/bin
+OSFLAGS                ?= -arch $(POCO_TARGET_OSARCH) -isysroot $(TVOS_SDK_BASE) -mtvos-version-min=$(TVOS_SDK_VERSION_MIN) -fembed-bitcode
+
+#
+# Tools
+#
+# If GCC_VER is defined then use it.
+# Otherwise select the latest version
+#
+
+CC		= $(shell xcrun -find clang)
+CXX		= $(shell xcrun -find clang++)
+
+LINK    = $(CXX) -bind_at_load
+LIB     = libtool -static -o
+RANLIB  = ranlib
+SHLIB   = $(CXX) $(OSFLAGS) -dynamiclib -Wl,-install_name,$@ -o $@
+DYLIB   = $(CXX) $(OSFLAGS) -dynamic -bundle -read_only_relocs suppress -Wl,-bind_at_load -o $@ 
+SHLIBLN = $(POCO_BASE)/build/script/shlibln
+STRIP   = 
+DEP     = $(POCO_BASE)/build/script/makedepend.gcc
+SHELL   = sh
+RM      = rm -rf
+CP      = cp
+MKDIR   = mkdir -p
+
+#
+# Extension for Shared Libraries
+#
+SHAREDLIBEXT     = .$(target_version).dylib
+SHAREDLIBLINKEXT = .dylib
+
+#
+# Compiler and Linker Flags
+#
+CFLAGS          = $(OSFLAGS) -std=gnu99
+CFLAGS32        =
+CFLAGS64        =
+CXXFLAGS        = $(OSFLAGS) -std=c++11 -stdlib=libc++ -Wall -Wno-sign-compare 
+CXXFLAGS32      =
+CXXFLAGS64      = 
+LINKFLAGS       = $(OSFLAGS) -stdlib=libc++
+LINKFLAGS32     =
+LINKFLAGS64     =
+STATICOPT_CC    =
+STATICOPT_CXX   =
+STATICOPT_LINK  =
+SHAREDOPT_CC    = -fPIC 
+SHAREDOPT_CXX   = -fPIC
+SHAREDOPT_LINK  = 
+DEBUGOPT_CC     = -g -D_DEBUG=$(DEBUGLEVEL)
+DEBUGOPT_CXX    = -g -D_DEBUG=$(DEBUGLEVEL) 
+DEBUGOPT_LINK   =
+RELEASEOPT_CC   = -DNDEBUG -O2
+RELEASEOPT_CXX  = -DNDEBUG -O 
+RELEASEOPT_LINK =
+
+#
+# System Specific Flags
+#
+SYSFLAGS = -DPOCO_HAVE_IPv6 -DPOCO_SOCKETADDRESS_DONT_PREFER_IPV4 -DPOCO_NO_FPENVIRONMENT -DPOCO_NO_STAT64 -DPOCO_NO_SHAREDLIBS -DPOCO_NO_NET_IFTYPES -DPOCO_NO_FORK_EXEC
+
+#
+# System Specific Libraries
+#
+SYSLIBS  = -ldl