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/PDF/samples/Template/Makefile

@@ -0,0 +1,15 @@
+#
+# Makefile
+#
+# Makefile for Poco PDF Template sample
+#
+
+include $(POCO_BASE)/build/rules/global
+
+objects = Template
+
+target         = Template
+target_version = 1
+target_libs    = PocoPDF PocoUtil PocoXML PocoFoundation
+
+include $(POCO_BASE)/build/rules/exec