[JENKINS-67313][JENKINS-72931] fix links (#310)

[JENKINS-67313] do not show a link in views for multibranch or org folder jobs.
[JENKINS-72931] To not show a link in the sidepanel for matrix
subprojects (axis)

src/main/java/org/jenkinsci/plugins/schedulebuild/ScheduleBuildButtonColumn.java

@@ -2,12 +2,19 @@
 
 import hudson.Extension;
 import hudson.model.Descriptor;
+import hudson.model.Job;
+import hudson.model.TopLevelItem;
 import hudson.views.ListViewColumn;
 import hudson.views.ListViewColumnDescriptor;
 import net.sf.json.JSONObject;
 import org.kohsuke.stapler.StaplerRequest;
 
 public class ScheduleBuildButtonColumn extends ListViewColumn {
+
+    public boolean isBuildable(TopLevelItem item) {
+        return item instanceof Job;
+    }
+
     public static final class DescriptorImpl extends ListViewColumnDescriptor {
         @Override
         public String getDisplayName() {

src/main/java/org/jenkinsci/plugins/schedulebuild/ScheduleBuildTransientProjectActionFactory.java

@@ -3,6 +3,7 @@
 import hudson.Extension;
 import hudson.model.Action;
 import hudson.model.Job;
+import hudson.model.TopLevelItem;
 import java.util.Collection;
 import java.util.Collections;
 import jenkins.model.TransientActionFactory;
@@ -17,6 +18,10 @@ public Class<Job> type() {
 
     @Override
     public Collection<? extends Action> createFor(Job target) {
-        return Collections.singleton(new ScheduleBuildAction(target));
+        if (target instanceof TopLevelItem) {
+            return Collections.singleton(new ScheduleBuildAction(target));
+        } else {
+            return Collections.emptyList();
+        }
     }
 }

src/main/resources/org/jenkinsci/plugins/schedulebuild/ScheduleBuildButtonColumn/column.jelly

@@ -1,7 +1,7 @@
 <?jelly escape-by-default='true'?>
 <j:jelly xmlns:j="jelly:core" xmlns:l="/lib/layout">
     <td class="jenkins-table__cell--tight">
-        <j:if test="${job.buildable and job.hasPermission(job.BUILD)}">
+        <j:if test="${it.isBuildable(job) and job.buildable and job.hasPermission(job.BUILD)}">
              <div class="jenkins-table__cell__button-wrapper">
                  <j:set var="href" value="${jobBaseUrl}${job.shortUrl}schedule"/>
                  <a href="${href}" tooltip="${%ScheduleBuildColumn.Title}" class="jenkins-table__button">