Add urlParse function (i.e. url.Parse)

Signed-off-by: Dave Henderson <dhenderson@gmail.com>

README.md

@@ -425,6 +425,27 @@ $ FOO="  world " | gomplate < input.tmpl
 Hello, world!
 ```
 
+#### `urlParse`
+
+Parses a string as a URL for later use. Equivalent to [url.Parse](https://golang.org/pkg/net/url/#Parse)
+
+##### Example
+
+_`input.tmpl`:_
+```
+{{ $u := urlParse "https://example.com:443/foo/bar" }}
+The scheme is {{ $u.Scheme }}
+The host is {{ $u.Host }}
+The path is {{ $u.Path }}
+```
+
+```console
+$ gomplate < input.tmpl
+The scheme is https
+The host is example.com:443
+The path is /foo/bar
+```
+
 #### `has`
 
 Has reports whether or not a given object has a property with the given key. Can be used with `if` to prevent the template from trying to access a non-existent property in an object.

gomplate.go

@@ -3,6 +3,7 @@ package main
 import (
 	"io"
 	"log"
+	"net/url"
 
 	"strings"
 	"text/template"
@@ -68,6 +69,7 @@ func NewGomplate(data *Data, leftDelim, rightDelim string) *Gomplate {
 			"toLower":          strings.ToLower,
 			"trim":             strings.Trim,
 			"trimSpace":        strings.TrimSpace,
+			"urlParse":         url.Parse,
 			"datasource":       data.Datasource,
 			"ds":               data.Datasource,
 			"datasourceExists": data.DatasourceExists,