CE Improve import status table UI

What does this MR do?

EE: https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/8707

Improve import status table UI, replace with vue app.

• Add "Go to project" button
• Align import buttons to the right
• Remove namespace select grey container
• Removing row status colour and use ci-style status icons to represent status

What are the relevant issue numbers?

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/14010

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• Tests added for this feature/bug
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• Conforms to the database guides

app/assets/javascripts/import_projects/components/import_projects_table.vue

+<script>
+import { mapActions, mapState, mapGetters } from 'vuex';
+import { GlLoadingIcon } from '@gitlab/ui';
+import ImportedProjectTableRow from './imported_project_table_row.vue';
+import ProviderRepoTableRow from './provider_repo_table_row.vue';
+import LoadingButton from '../../vue_shared/components/loading_button.vue';
+import eventHub from '../event_hub';
+
+export default {
+  name: 'ImportProjectsTable',
+
+  components: {
+    ImportedProjectTableRow,
+    ProviderRepoTableRow,
+    LoadingButton,
+    GlLoadingIcon,
+  },
+
+  props: {
+    providerTitle: {
+      type: String,
+      required: true,
+    },
+  },
+
+  computed: {
+    ...mapState(['importedProjects', 'providerRepos', 'isLoadingRepos']),
+    ...mapGetters(['isImportingAnyRepo', 'hasProviderRepos', 'hasImportedProjects']),
+
+    emptyStateText() {
+      const emptyStateText = this.__('No  %{providerTitle} repositories available to import');
+
+      return this.sprintf(emptyStateText, { providerTitle: this.providerTitle });
+    },
+
+    fromHeaderText() {
+      return this.sprintf(this.__('From %{providerTitle}'), { providerTitle: this.providerTitle });
+    },
+  },
+
+  mounted() {
+    return this.fetchRepos().then(this.pollJobs);
+  },
+
+  methods: {
+    ...mapActions(['fetchRepos', 'pollJobs']),
+
+    importAll() {
+      eventHub.$emit('importAll');
+    },
+  },
+};
+</script>
+
+<template>
+  <div>
+    <div class="d-flex justify-content-between align-items-end flex-wrap mb-3">
+      <p class="light text-nowrap mt-2 my-sm-0">
+        {{ s__('ImportProjects|Select the projects you want to import') }}
+      </p>
+      <loading-button
+        container-class="btn btn-success js-import-all"
+        :loading="isImportingAnyRepo"
+        :label="__('Import all repositories')"
+        :disabled="!hasProviderRepos"
+        type="button"
+        @click="importAll"
+      />
+    </div>
+    <gl-loading-icon
+      v-if="isLoadingRepos"
+      class="js-loading-button-icon import-projects-loading-icon"
+      :size="4"
+    />
+    <div v-else-if="hasProviderRepos || hasImportedProjects" class="table-responsive">
+      <table class="table import-table">
+        <thead>
+          <th class="import-jobs-from-col">{{ fromHeaderText }}</th>
+          <th class="import-jobs-to-col">{{ __('To GitLab') }}</th>
+          <th class="import-jobs-status-col">{{ __('Status') }}</th>
+          <th class="import-jobs-cta-col"></th>
+        </thead>
+        <tbody>
+          <imported-project-table-row
+            v-for="project in importedProjects"
+            :key="project.id"
+            :project="project"
+          />
+          <provider-repo-table-row v-for="repo in providerRepos" :key="repo.id" :repo="repo" />
+        </tbody>
+      </table>
+    </div>
+    <div v-else class="text-center">
+      <strong>{{ emptyStateText }}</strong>
+    </div>
+  </div>
+</template>