Update bashbrew to Go 1.13 + Alpine 3.10, update manifest-tool to v1.0.0 🎉

bashbrew/Dockerfile.release

@@ -1,4 +1,4 @@
-FROM golang:1.12-alpine3.9
+FROM golang:1.13-alpine3.10
 
 RUN apk add --no-cache \
 		file \
@@ -22,7 +22,7 @@ ENV BASHBREW_ARCHES \
 COPY .bashbrew-arch-to-goenv.sh /usr/local/bin/
 
 # https://github.com/estesp/manifest-tool/releases
-ENV MANIFEST_TOOL_VERSION 1.0.0-rc
+ENV MANIFEST_TOOL_VERSION 1.0.0
 # gpg: key 0F386284C03A1162: public key "Philip Estes <[email protected]>" imported
 ENV MANIFEST_TOOL_GPG_KEY 27F3EA268A97867EAF0BD05C0F386284C03A1162