api_template doesn't get shown correctly in peep

[sckott]

works correctly for similar api_path function, but doesn't for api_template, eg..,

repo_info <- list(username = 'craigcitro', repo = 'r-travis')
api('https://api.github.com/') %>%
    api_template(template = 'repos/{{username}}/{{repo}}/issues', data = repo_info) %>% 
    peep
#> <http request> 
#>   url: https://api.github.com/
#>   paths: ## should be shown here
#>   query: 
#>   body: 
#>   paging: 
#>   headers: 
#>   rate limit: 
#>   retry (n/delay (s)): /
#>   error handler: 
#>   config: