build: include docs link in README and build system

Makefile.am

@@ -60,7 +60,21 @@ EXTRA_DIST =	pkg.m4 \
 		tests/lib1/provides.pc \
 		tests/lib1/provides-request-simple.pc \
 		tests/test_env.sh \
-		$(test_scripts)
+		$(test_scripts) \
+		doc/conf.py \
+		doc/extract.py \
+		doc/index.rst \
+		doc/libpkgconf.rst \
+		doc/libpkgconf-argvsplit.rst \
+		doc/libpkgconf-audit.rst \
+		doc/libpkgconf-cache.rst \
+		doc/libpkgconf-client.rst \
+		doc/libpkgconf-dependency.rst \
+		doc/libpkgconf-fragment.rst \
+		doc/libpkgconf-path.rst \
+		doc/libpkgconf-pkg.rst \
+		doc/libpkgconf-queue.rst \
+		doc/libpkgconf-tuple.rst
 
 test_scripts=	\
 		tests/basic.sh \

README.md

@@ -1,4 +1,4 @@
-# pkgconf [![Build Status](https://travis-ci.org/pkgconf/pkgconf.svg?branch=master)](https://travis-ci.org/pkgconf/pkgconf)
+# pkgconf [![Build Status](https://travis-ci.org/pkgconf/pkgconf.svg?branch=master)](https://travis-ci.org/pkgconf/pkgconf) [![Documentation Status](https://readthedocs.org/projects/pkgconf/badge/?version=latest)](http://pkgconf.readthedocs.io/en/latest/?badge=latest)
 
 `pkgconf` is a program which helps to configure compiler and linker flags for
 development frameworks.  It is similar to pkg-config from freedesktop.org.