add(taskwarrior): pull implementation for new tasks

This implements the pull functionality for new tasks, which are not yet
in the local taskwarrior instance created. WIP for #3.

internal/gitea/issue.go

@@ -13,6 +13,11 @@ type PullRequest struct {
 	Merged_at time.Time `json:"merged_at"`
 }
 
+type IssueState string
+
+const CLOSED IssueState = "closed"
+const OPEN IssueState = "open"
+
 type Issue struct {
 	Id                 uint        `json:"id"`
 	Url                string      `json:"url"`
@@ -104,7 +109,7 @@ func (gitea *Gitea) NewIssue(repo Repository, issue Issue) (Issue, error) {
 	payload["assignee"] = issue.Assignee
 	payload["assignees"] = issue.Assignees
 	payload["body"] = issue.Body
-	payload["closed"] = issue.State == "closed"
+	payload["closed"] = issue.State == string(CLOSED)
 	payload["due_date"] = issue.Due_date
 	payload["lables"] = issue.Labels
 	payload["milestone"] = issue.Milestone.Title != ""