Move get_instance from CodeRepo to DocRepo

[#65032326]

Signed-off-by: Dan Wendorf <dwendorf@pivotallabs.com>
Make Repository initializable [#65032326]

Signed-off-by: Dan Wendorf <dwendorf@pivotallabs.com>
Move DocRepo#copy_from_local and #copied? to Repository

[#65032326]

Signed-off-by: Dan Wendorf <dwendorf@pivotallabs.com>
Move DocRepo#has_tag? to Repository

Move tests for Repository#tag_with to repository_spec

[#65032326]

Signed-off-by: Dan Wendorf <dwendorf@pivotallabs.com>
UpdateLocalDocRepos no longer delegates to LocalDocReposUpdater.

Signed-off-by: Dan Wendorf <dwendorf@pivotallabs.com>
DocRepo#get_instance takes a repo_hash

Signed-off-by: Gavin Morgan <gavin@pivotallabs.com>
Instantiate DocRepo exclusively through .get_instance

[#65032326]

Signed-off-by: Gavin Morgan <gavin@pivotallabs.com>
Remove useless let in spec

Signed-off-by: Gavin Morgan <gavin@pivotallabs.com>
DocRepo no longer inherits from Repository

[#65032326]

Signed-off-by: Gavin Morgan <gavin@pivotallabs.com>
Renames CodeRepo > CodeExample and DocRep > Chapter

Signed-off-by: Gavin Morgan <gavin@pivotallabs.com>
Repositories build themselves

Signed-off-by: Gavin Morgan <gavin@pivotallabs.com>
Book does not inherit from Repository

Signed-off-by: Gavin Morgan <gavin@pivotallabs.com>
CredentialProvider (nee CredRepo) does not inherit from Repository

Signed-off-by: Gavin Morgan <gavin@pivotallabs.com>