add visc_load_pdata function to keep in a centralized location

[valduran18]

Closes issue #146. @slager @lemireg please review when you can

[lemireg]

Looking at the "Files Changed" tab this looks great! Glad to see this function in a centralized location.

To clarify @valduran18: this will not put visc_load_pdata into the individual datapackages or analysis repos, but it will allow individuals to copy the validated version of this file into their individual repositories (whether it's a datapackage the STP is working on or the analysis repo the SRA is working on?)

If so, I will add the location of this file in the powerpoint discussing how to incorporate it into analysis repos.

[slager]

@lemireg

This will typically be used as follows, so knowing the URL of this script shouldn't be necessary:

remotes::install_github('FredHutch/VISCtemplates') # first time only
remotes::install_local('/networks/cavd/Studies/cvd820/pdata/Caskey820.git') # first time you need the data package only
library(VISCtemplates)
library(Caskey820)
Caskey820_bama <- visc_load_pdata(Caskey820_bama_bds, criteria = "5d3fe6542a3a6517bdb2dc9e6b644d74")
... analysis using the `Caskey820_bama` variable now in your R global workspace ...

[lemireg]

@lemireg

This will typically be used as follows, so knowing the URL of this script shouldn't be necessary:

remotes::install_github('FredHutch/VISCtemplates') # first time only
remotes::install_local('/networks/cavd/Studies/cvd820/pdata/Caskey820.git') # first time you need the data package only
library(VISCtemplates)
library(Caskey820)
Caskey820_bama <- visc_load_pdata(Caskey820_bama_bds, criteria = "5d3fe6542a3a6517bdb2dc9e6b644d74")
... analysis using the `Caskey820_bama` variable now in your R global workspace ...

Very neat! Even more nifty than I thought. Great, I will start implementing this, thank you.