manifest: Update README with Gerrit commands

Submitting Patches

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Patches are always welcome!  Please send pull requests with your patches!  If at all possible please rebase your

repository before sending a pull request.  You can do this by using the following command:

Patches are always welcome!  Please submit your patches via CyanogenMod Gerrit!

You can do this by using these commands:

    git pull --rebase git://github.com/CyanogenMod/path_to_project.git gingerbread

    (From root android directory)

    . build/envsetup.sh

    (Go to repo you are patching, make your changes and commit)

    cmgerrit <for(new)/changes(patch set)> <branch/change-id> 

    repo start gingerbread .

    (Make your changes and commit)

    repo upload .

Note: "." meaning current directory

For more help on using this tool, use this command: repo help upload

Make your changes and commit with a detailed message, starting with what you are working with (i.e. vision: Update Kernel)

Commit your patches in a single commit. Squash multiple commit using this command: git rebase -i HEAD~<# of commits>

To view the status of your and others' patches, visit [CyanogenMod Code Review](http://review.cyanogenmod.com/)

This makes accepting patches MUCH easier for our comitters.

Getting Started

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