updating checksums to checksum and using drone.StringSlice instead of []string

DOCS.md

@@ -3,7 +3,7 @@ can override the default configuration with the following parameters:
 
 * `api_key` - GitHub oauth token with public_repo or repo permission
 * `files` - Files to upload to GitHub Release, globs are allowed
-* `checksums` - Checksum hashes to include in your GitHub release for all files specified. Supported hash methods include md5, sha1, sha256, sha512, adler32, and crc32.
+* `checksum` - Checksum takes hash methods to include in your GitHub release for the files specified. Supported hash methods include md5, sha1, sha256, sha512, adler32, and crc32.
 * `base_url` - GitHub base URL, only required for GHE
 * `upload_url` - GitHub upload URL, only required for GHE
 
@@ -15,7 +15,18 @@ publish:
     api_key: my_github_api_key
     files:
       - dist/*
-    checksums:
+    checksum: sha1
+```
+
+or
+
+```yaml
+publish:
+  github_release:
+    api_key: my_github_api_key
+    files:
+      - dist/*
+    checksum:
       - md5
       - sha1
       - sha256

README.md

@@ -32,7 +32,7 @@ Drone plugin for publishing GitHub releases
             "dist/*.txt",
             "dist/other-file"
         ],
-        "checksums": [
+        "checksum": [
             "md5",
             "sha1",
             "sha256",
@@ -80,7 +80,7 @@ docker run -i plugins/drone-github-release <<EOF
             "dist/*.txt",
             "dist/other-file"
         ],
-        "checksums": [
+        "checksum": [
             "md5",
             "sha1",
             "sha256",

main.go

@@ -71,9 +71,9 @@ func main() {
 		}
 	}
 
-	if len(vargs.Checksums) > 0 {
+	if vargs.Checksum.Len() > 0 {
 		var err error
-		files, err = writeChecksums(files, vargs.Checksums)
+		files, err = writeChecksums(files, vargs.Checksum.Slice())
 		if err != nil {
 			fmt.Println(err)
 			os.Exit(1)

types.go

@@ -1,10 +1,12 @@
 package main
 
+import "github.com/drone/drone-go/drone"
+
 // Params are the parameters that the GitHub Release plugin can parse.
 type Params struct {
-	BaseURL   string   `json:"base_url"`
+	BaseURL   string            `json:"base_url"`
-	UploadURL string   `json:"upload_url"`
+	UploadURL string            `json:"upload_url"`
-	APIKey    string   `json:"api_key"`
+	APIKey    string            `json:"api_key"`
-	Files     []string `json:"files"`
+	Files     []string          `json:"files"`
-	Checksums []string `json:"checksums"`
+	Checksum  drone.StringSlice `json:"checksum"`
 }