Beging to work on issue gogs#3201

Author: Tomash Sidei

conf/locale/locale_en-US.ini

@@ -520,6 +520,7 @@ pulls.is_checking = The conflict checking is still in progress, please refresh p
 pulls.can_auto_merge_desc = This pull request can be merged automatically.
 pulls.cannot_auto_merge_desc = This pull request can't be merged automatically because there are conflicts.
 pulls.cannot_auto_merge_helper = Please merge manually in order to resolve the conflicts.
+pulls.delete_source_branch = Delete Source Branch
 pulls.merge_pull_request = Merge Pull Request
 pulls.open_unmerged_pull_exists = `You can't perform reopen operation because there is already an open pull request (#%d) from same repository with same merge information and is waiting for merging.`
 

templates/repo/issue/view_content.tmpl

@@ -175,6 +175,12 @@
 									<div>
 										<form class="ui form" action="{{.Link}}/merge" method="post">
 											{{.CsrfTokenHtml}}
+											<div class="field">
+												<div class="ui checkbox">
+													<input type="checkbox" name="example">
+													<label> {{$.i18n.Tr "repo.pulls.delete_source_branch"}} </label>
+												</div>
+											</div>
 											<button class="ui green button">
 												<span class="octicon octicon-git-merge"></span> {{$.i18n.Tr "repo.pulls.merge_pull_request"}}
 											</button>