Documentation: git-rebase discussion, miscellaneous user-manual updates
Documentation: git-rebase discussion, miscellaneous user-manual updates

Add discussion of git-rebase, patch series, history rewriting.

Mention "pull ." as a synonym for "merge".

Remind myself of another case I want to cover in the other-vcs's chapter.

Signed-off-by: "J. Bruce Fields" <51738506c1b2ccb0761f23bdc612c93babf738ea@citi.umich.edu>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git