Add hypermean() and hypersd() functions

[dannytoomey]

Hi Witold,

Here's a pull request that resolves issue #145. I added hypermean() and hypersd() functions that return values equal to treatment_effect[[1]] and treatment_effect[[2]] respectively and updated the package to use these functions were applicable.

I also stumbled across an unrelated error while testing. I ran bg <- baggr(microcredit_simplified, model = "quantiles",quantiles = c(0.25, 0.50, 0.75),iter = 1000, refresh = 0,outcome = "consumption") and got this error: Error in out$Nc <- 0 : object 'out' not found

Would you like me to add this to the list? I took a brief look and think the error may be thrown by stan, though the traceback was a bit ambiguous.

Best regards,

Danny Toomey

[wwiecek]

Kill this commit and make a fresh one (1) making the same changes but without .so file (2) or purge .so file from history, but this can be more tricky (wouldn't recommend) (3) or cherry pick changes to the relevant files only (like (1) but can be done via git)

In this case you also committed src/Makevars, please don't do that