update README to show get_cran() refresh

also update  the data in the metrics_table example, add Colin as contributor

DESCRIPTION

@@ -6,7 +6,9 @@ Authors@R: c(person("Sam", "Firke", email = "samuel.firke@gmail.com", role = c("
              person("Erin", "Grand", email = "eringrand@gmail.com", role = "aut"),
              person("Lori", "Shepherd", email = "lori.shepherd@roswellpark.org", role = "aut"),
              person("William","Ampeh", email = "wampeh@gmu.edu", role = "aut"),
-             person("Hannah", "Frick", email = "hannah.frick@gmail.com", role = "aut"))
+             person("Hannah", "Frick", email = "hannah.frick@gmail.com", role = "aut"),
+             person("Gillespie", "Colin", email = "csgillespie+github@gmail.com", role = "ctb"))
+
 Description: This package was designed to address two issues, 78 and 69, for the ROpenSci unconf17 concerning avoiding redundant / overlapping packages and a framework for reproducible tables. As this is a complex topic, the smaller tasks being accomplished is producing a list of metrics that can be used to compare similar packages utilizing information collected from CRAN, GitHub, and StackOverflow.
 Depends: R (>= 3.4.0)
 Imports:

README.Rmd

@@ -22,12 +22,22 @@ devtools::install_github("ropenscilabs/packagemetrics")
 
 ## Use
 
-### Here's an example using a case study of popular table-making packages.  
+**Comparing dplyr and data.table:**
 
 ```{r, echo=TRUE}
 library(packagemetrics)
+library(dplyr)
 
-pkg_df <- package_list_metrics(table_packages)
+dplyr_and_dt <- package_list_metrics(c("dplyr", "data.table"))
+glimpse(dplyr_and_dt)
+```
+
+### Creating a pretty metrics_table
+
+Here's a comparison of popular table-making packages, using the `metrics_table` function:
+
+```{r, echo = TRUE}
+pkg_df <- package_list_metrics(table_packages) # included vector of table pkgs
 ft <- metrics_table(pkg_df)
 ```
 
@@ -41,6 +51,12 @@ webshot::webshot(url,
                  delay = 0.2)
 ```
 
+## Refreshing data sources
+
+If the cached CRAN data gets out of date, call `get_cran(forget = TRUE)` to force refreshing.  This will fetch the latest results from CRAN and cache them for use going forward.
+
+GitHub data is scraped at the time of the call to `package_list_metrics`.
+
 ## Requirements
 
 ```packagemetrics``` requires R version >= 3.4.0.

README.md

@@ -21,16 +21,54 @@ devtools::install_github("ropenscilabs/packagemetrics")
 Use
 ---
 
-### Here's an example using a case study of popular table-making packages.
+**Comparing dplyr and data.table:**
 
 ``` r
 library(packagemetrics)
+library(dplyr)
 
-pkg_df <- package_list_metrics(table_packages)
+dplyr_and_dt <- package_list_metrics(c("dplyr", "data.table"))
+glimpse(dplyr_and_dt)
+```
+
+    ## Observations: 2
+    ## Variables: 18
+    ## $ package            <chr> "dplyr", "data.table"
+    ## $ published          <chr> "2017-09-28", "2017-10-27"
+    ## $ title              <chr> "A Grammar of Data Manipulation", "Extensio...
+    ## $ depends_count      <int> 1, 1
+    ## $ suggests_count     <int> 17, 18
+    ## $ tidyverse_happy    <lgl> TRUE, FALSE
+    ## $ has_vignette_build <lgl> TRUE, TRUE
+    ## $ has_tests          <lgl> TRUE, TRUE
+    ## $ reverse_count      <int> 677, 377
+    ## $ dl_last_month      <dbl> 393520, 286717
+    ## $ ci                 <chr> "Travis, Appveyor", "NONE"
+    ## $ test_coverage      <chr> "CodeCov", NA
+    ## $ forks              <dbl> 836, 650
+    ## $ stars              <dbl> 2097, 1253
+    ## $ watchers           <dbl> 236, 156
+    ## $ last_commit        <dbl> 0.66666667, 0.06666667
+    ## $ last_issue_closed  <dbl> 0.06666667, 0.10000000
+    ## $ contributors       <dbl> 136, 43
+
+### Creating a pretty metrics\_table
+
+Here's a comparison of popular table-making packages, using the `metrics_table` function:
+
+``` r
+pkg_df <- package_list_metrics(table_packages) # included vector of table pkgs
 ft <- metrics_table(pkg_df)
 ```
 
-![](README_files/figure-markdown_github-ascii_identifiers/unnamed-chunk-2-1.png)
+![](README_files/figure-markdown_github/unnamed-chunk-3-1.png)
+
+Refreshing data sources
+-----------------------
+
+If the cached CRAN data gets out of date, call `get_cran(forget = TRUE)` to force refreshing. This will fetch the latest results from CRAN and cache them for use going forward.
+
+GitHub data is scraped at the time of the call to `package_list_metrics`.
 
 Requirements
 ------------