Add theme eject command #247

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Feature request

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Add saber eject, similar to vuepress eject to copy over the currently used theme from node_modules or from Github (perhaps as a submodule) to theme and change the config file accordingly.

What problem does this feature solve?

Allows modification of installed themes.

What does the proposed API look like?

saber eject

How should this be implemented in your opinion?

Give the user the choice whether to use the perhaps precompiled files from node_modules or to clone the theme's repo as a submodule.

Are you willing to work on this yourself?

Yes.