WIP documentation

- The documentation is cluttered enough as it is with the large number
  of procedures supporting vCard 3 and 4. Split common out into the
  publicly exposed bits and the private internals. This makes it obvious
  which common functionality a client can expect to have exposed on the
  main vcard module.

- Add documentation (WIP) on the vcard3 module.

Makefile

@@ -1,13 +1,18 @@
 # Make does not offer a recursive wildcard function, so here's one:
- rwildcard=$(wildcard $1$2) $(foreach d,$(wildcard $1*),$(call rwildcard,$d/,$2))
+rwildcard=$(wildcard $1$2) $(foreach d,$(wildcard $1*),$(call rwildcard,$d/,$2))
 
 SOURCES=$(call rwildcard,src/,*.nim)
 TEST_SOURCES=$(wildcard tests/*.nim)
 TESTS=$(patsubst %.nim,bin/%,$(TEST_SOURCES))
 
 .PHONY: build
-build: test
-	nimble build
+build: test docs
+
+doc/vcard/vcard.html: $(SOURCES)
+	nim doc --project --outdir:doc/vcard src/vcard.nim
+
+.PHONY: doc
+docs: doc/vcard/vcard.html
 
 .PHONY: test
 test: