[Doc] Added Centos 7 Dependency Commands

[Kavex]

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Short Description:

Added commands tot he Docs for CentOS 7 Dependency to make it easier to install them

Fixes/Resolves/Closes (please use correct syntax):

• [Doc] Added sudo yum install -y epel-release
• [Doc] Added sudo yum install -y git wget python python-pip
• [Doc] Added sudo yum groupinstall -y "Development Tools"

[Doc] Added Centos 7 Dependency Commands

[mention-bot]

@Kavex, thanks for your PR! By analyzing the history of the files in this pull request, we identified @nivong, @danielsdian and @nelsyeung to be potential reviewers.