debian: package HTML docs

This is particularly useful for the docs for the notmuch2 python
bindings, which are otherwise not packaged.

debian/control

@@ -56,7 +56,8 @@ Recommends:
  gnupg-agent,
  gpgsm,
 Suggests:
- mailscripts
+ mailscripts,
+ notmuch-doc,
 Description: thread-based email index, search and tagging
  Notmuch is a system for indexing, searching, reading, and tagging
  large collections of email messages in maildir or mh format. It uses
@@ -65,6 +66,21 @@ Description: thread-based email index, search and tagging
  .
  This package contains the notmuch command-line interface
 
+Package: notmuch-doc
+Architecture: all
+Depends:
+ ${misc:Depends},
+ ${sphinxdoc:Depends},
+Suggests:
+ notmuch
+Description: thread-based email index, search and tagging
+ Notmuch is a system for indexing, searching, reading, and tagging
+ large collections of email messages in maildir or mh format. It uses
+ the Xapian library to provide fast, full-text search with a very
+ convenient search syntax.
+ .
+ This package contains the HTML documentation
+
 Package: libnotmuch5
 Section: libs
 Architecture: any

debian/rules

@@ -3,7 +3,7 @@
 export DEB_BUILD_MAINT_OPTIONS = hardening=+all
 
 %:
-	dh $@ --with python3,elpa
+	dh $@ --with python3,elpa,sphinxdoc
 
 override_dh_auto_configure:
 	BASHCMD=/bin/bash ./configure --prefix=/usr \
@@ -19,7 +19,7 @@ override_dh_auto_test:
 	dh_auto_test -- V=1
 
 override_dh_auto_build:
-	dh_auto_build -- V=1
+	dh_auto_build -- V=1 all sphinx-html
 	PYBUILD_NAME=notmuch dh_auto_build --buildsystem=pybuild --sourcedirectory bindings/python
 	PYBUILD_NAME=notmuch2 dh_auto_build --buildsystem=pybuild --sourcedirectory bindings/python-cffi
 	$(MAKE) -C contrib/notmuch-mutt