docs: update docs for 0.4.0 release

- Add Dragonwell and Skeleton images in reference container image
- Update Version number
Signed-off-by: NShirong Hao <shirong@linux.alibaba.com>

README.md

@@ -68,5 +68,5 @@ Please refer to [this guide](docs/develop_and_deploy_hello_world_application_in_
 ---
 
 ## Reference container image
-[The reference container images](https://hub.docker.com/u/inclavarecontainers) are available for the demonstration purpose to show how a Confidential Computing Kubernetes Cluster with Inclavare Containers works. Currently, web application demos based on OpenJDK 11 and Golang are provided.
+[The reference container images](https://hub.docker.com/u/inclavarecontainers) are available for the demonstration purpose to show how a Confidential Computing Kubernetes Cluster with Inclavare Containers works. Currently, web application demos based on OpenJDK 11, Dragonwell, and Golang are provided.
 

docs/running_rune_with_occlum.md

@@ -96,7 +96,7 @@ rpm -ivh occlum-pal-0.15.1-1.el8.x86_64.rpm
 - On Ubuntu 18.04-server:
 ```shell
 dpkg -i rune_0.4.0-1_amd64.deb
-dpkg -i occlum-pal_0.15.1_amd64.deb
+dpkg -i occlum-pal_0.15.1-1_amd64.deb
 ```
 
 ---

rune/libenclave/internal/runtime/pal/skeleton/README.md

@@ -35,6 +35,8 @@ EOF
 docker build . -t skeleton-enclave
 ```
 
+[Skeleton container image](https://hub.docker.com/r/inclavarecontainers/skeleton-enclave/tags) is available for the demonstration purpose.
+
 ## Build and install rune
 Please refer to [this guide](https://github.com/alibaba/inclavare-containers#rune) to build `rune` from scratch.
 

sgx-tools/README.md

@@ -7,10 +7,10 @@
 
 ## Install Intel `aesmd` service
 ### Hardware requirements
-- Install [Intel SGX driver for Linux](https://github.com/intel/linux-sgx-driver#build-and-install-the-intelr-sgx-driver), required by [Intel SGX SDK && PSW](https://github.com/intel/linux-sgx).
+- Install Intel SGX driver for Linux by following [Intel SGX Installation Guide](https://download.01.org/intel-sgx/sgx-linux/2.9.1/docs/Intel_SGX_Installation_Guide_Linux_2.9.1_Open_Source.pdf), required by [Intel SGX SDK && PSW](https://github.com/intel/linux-sgx).
 
 ### Software requirements
-- Build [Intel(R) SGX SDK and Intel(R) SGX PSW](https://github.com/intel/linux-sgx#build-the-intelr-sgx-sdk-and-intelr-sgx-psw-package) to install the `aesmd` service.
+- Build Intel(R) SGX SDK and Intel(R) SGX PSW by following [Intel SGX Installation Guide](https://download.01.org/intel-sgx/sgx-linux/2.9.1/docs/Intel_SGX_Installation_Guide_Linux_2.9.1_Open_Source.pdf) to install the `aesmd` service.
 
 ## Dependency
 - golang 1.14 or above.