doc: generate man page

This commit uses the recent refactoring for defining flags to
automatically generate a man page. This finally allows us to define the
documentation for each flag in a single place.

The man page is generated on every build, if and only if `asciidoc` is
installed. When generated, it is placed in Cargo's `OUT_DIR` directory,
which is the same place that shell completions live.

ci/before_deploy.sh

@@ -20,17 +20,25 @@ mk_tarball() {
     local gcc_prefix="$(gcc_prefix)"
     local td="$(mktemp -d)"
     local name="${PROJECT_NAME}-${TRAVIS_TAG}-${TARGET}"
-    mkdir -p "$td/$name/complete"
-    mkdir deployment
+    local staging="$td/$name"
+    mkdir -p "$staging/complete"
     local out_dir="$(pwd)/deployment"
+    mkdir -p "$out_dir"
 
-    cp target/$TARGET/release/rg "$td/$name/rg"
-    "${gcc_prefix}strip" "$td/$name/rg"
-    cp {doc/rg.1,README.md,UNLICENSE,COPYING,LICENSE-MIT} "$td/$name/"
+    # Copy the ripgrep binary and strip it.
+    cp target/$TARGET/release/rg "$staging/rg"
+    "${gcc_prefix}strip" "$staging/rg"
+    # Copy the README and licenses.
+    cp {README.md,UNLICENSE,COPYING,LICENSE-MIT} "$staging/"
+    # Copy shell completion files.
     cp \
       target/"$TARGET"/release/build/ripgrep-*/out/{rg.bash,rg.fish,_rg.ps1} \
-      "$td/$name/complete/"
+      "$staging/complete/"
     cp complete/_rg "$td/$name/complete/"
+    # Copy man page.
+    cp \
+      target/"$TARGET"/release/build/ripgrep-*/out/rg.1 \
+      "$td/$name/"
 
     (cd "$td" && tar czf "$out_dir/$name.tar.gz" *)
     rm -rf "$td"