add demo animation image

Dockerfile

@@ -7,7 +7,7 @@ LABEL maintainer="Haruai Tamada" \
 
 RUN    adduser -D wildcat \
     && apk --no-cache add --update --virtual .builddeps curl tar \
-    && curl -s -L -O https://github.com/tamada/wildcat/releases/download/v{version}/wildcat-${version}_linux_amd64.tar.gz \
+    && curl -s -L -O https://github.com/tamada/wildcat/releases/download/v${version}/wildcat-${version}_linux_amd64.tar.gz \
 #    && curl -s -L -o wildcat-${version}_linux_amd64.tar.gz https://www.dropbox.com/s/f8in5s80q56s05m/wildcat-${version}_linux_amd64.tar.gz?dl=0 \
     && tar xfz wildcat-${version}_linux_amd64.tar.gz     \
     && mv wildcat-${version} /opt                        \

README.md

@@ -36,6 +36,8 @@ Note that this product is an example project for implementing Open Source Softwa
 
 ## :walking: Demo
 
+![demo](docs/static/images/demo.gif)
+
 ## :runner: Usage
 
 ### :shoe: CLI mode

docs/content/_index.md

@@ -29,3 +29,7 @@ The excellent points than `wc` are as follows.
 * includes REST API server.
 
 Note that this product is an example project for implementing Open Source Software.
+
+## :fire: Demo
+
+![Demo](images/demo.gif)

go.sum

@@ -8,6 +8,7 @@ github.com/sabhiram/go-gitignore v0.0.0-20201211210132-54b8a0bf510f h1:8P2MkG70G
 github.com/sabhiram/go-gitignore v0.0.0-20201211210132-54b8a0bf510f/go.mod h1:+ePHsJ1keEjQtpvf9HHw0f4ZeJ0TLRsxhunSI2hYJSs=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+github.com/stretchr/objx v0.1.0 h1:4G4v2dO3VZwixGIRoQ5Lfboy6nUhCyYzaqnIAPPhYs4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=