Add GNUmakefile to build a Zip of PDFs and release it to GitHub

.gitignore

@@ -34,3 +34,4 @@
 *.tdo
 hpmor-*.pdf
 hpmor.pdf
+hpmor*.zip

GNUmakefile

@@ -0,0 +1,18 @@
+# Make a PDF release
+
+PROJECT=hpmor
+
+TAG := $(shell git describe --tags)
+VERSION := $(shell echo $(TAG) | sed -e 's/^v//')
+ZIPFILE = $(PROJECT)-$(VERSION).zip
+
+all:
+	latexmk -g && \
+	rm -f $(ZIPFILE) && \
+	zip $(ZIPFILE) *.pdf
+
+# To make a release: git tag vx.y && git push --tags && make release
+# Needs woger from https://github.com/rrthomas/woger/
+release: all
+	git diff --exit-code && \
+	woger github github_user=rjl20 package=$(PROJECT) version=$(VERSION) dist_type=zip github_dist_type=pdf

README.md

@@ -27,12 +27,15 @@ and there are no appendices.
   individual volumes `hpmor-N.tex`.
 * `fonts/` - various fonts used
 * `latexmkrc` - configures latexmk to run LaTeX to build the PDFs.
+* `GNUMakefile` - contains targets to make a Zip of the PDFs and release them
+  to GitHub. (Mostly of interest to project maintainers.)
 
 
 ## Building the book(s)
 
 * `latexmk`: Build all PDFs. (If in doubt, just run this command and do
   something else for twenty minutes!)
+* `make all`: Build a Zip of the PDFs.
 * `latexmk hpmor`: Build the one-volume PDF `hpmor.pdf`
 * `latexmk hpmor-N`: Build one of the six individual volumes
   `hpmor-1.pdf` to `hpmor-6.pdf`.