branch option

[graemeblair]

Thanks for this terrifically useful package.

The branch that drat commits, gh-pages, is hardcoded. This is sensible in general, but for user or organization Github pages (i.e. user.github.io) Github requires those files to be stored in the master branch of a repo named user.github.io. Because of the hardcoding, it isn't possible to use drat to create a drat repo in such a Github repo.

What do you think of adding a field in insertPackage() for branch name, i.e. insertPackage(branch = "master")? Happy to add a PR.

[eddelbuettel]

a repo named user.github.io.

I think that had come up before and there was a reason not to do it. Maybe it was mostly because 'user.github.io' webpages don't correspond to the 'github.com/user/drat' scheme.

In any event one other (newer) change is worth considering too: master branch and docs/ directory. That is now permitted as an alternative.

The one thing I am a little wary about is the number of different code paths over the different helper functions. We'd need at least initRepo() and insertPackage() changed.

[eddelbuettel]

This too is now talken care of thank to @nfultz

[dracodoc]

gh-pages is still hard-coded in initRepo. Is it supposed to come from option dratBranch now? I didn't this option is set by default.

I think an option is fine for this, but initRepo and insertPackage should also provide a parameter for one time settings.

[dracodoc]

Added via #73

[eddelbuettel]

If you are suggesting a minimal (two file, maybe?) PR to add support for getOption("dratBranch", "gh-pages") to initRepo()then I would be favour as it works well enough in the existing functioninsertPackage()`.

[dracodoc]

The extreme minimal changes can be made with only changing initRepo and its .Rd file. However I felt it's easier to make one time adjustment for branch name with a parameter instead of options.

The default value still use options, so previous usage will not be interfered.