add saveTagsAlphabetically option

browser/main/Detail/MarkdownNoteDetail.js

@@ -363,6 +363,7 @@ class MarkdownNoteDetail extends React.Component {
         <TagSelect
           ref='tags'
           value={this.state.note.tags}
+          saveTagsAlphabetically={config.ui.saveTagsAlphabetically}
           showTagsAlphabetically={config.ui.showTagsAlphabetically}
           onChange={this.handleUpdateTag.bind(this)}
         />

browser/main/Detail/SnippetNoteDetail.js

@@ -744,6 +744,7 @@ class SnippetNoteDetail extends React.Component {
         <TagSelect
           ref='tags'
           value={this.state.note.tags}
+          saveTagsAlphabetically={config.ui.saveTagsAlphabetically}
           showTagsAlphabetically={config.ui.showTagsAlphabetically}
           onChange={(e) => this.handleChange(e)}
         />

browser/main/Detail/TagSelect.js

@@ -82,8 +82,14 @@ class TagSelect extends React.Component {
     value = _.isArray(value)
       ? value.slice()
       : []
-    value.push(newTag)
-    value = _.uniq(value)
+
+    if (!_.includes(value, newTag)) {
+        value.push(newTag)
+    }
+
+    if (this.props.saveTagsAlphabetically) {
+      value = _.sortBy(value)
+    }
 
     this.setState({
       newTag: ''

browser/main/modals/PreferencesModal/UiTab.js

@@ -71,6 +71,7 @@ class UiTab extends React.Component {
         confirmDeletion: this.refs.confirmDeletion.checked,
         showOnlyRelatedTags: this.refs.showOnlyRelatedTags.checked,
         showTagsAlphabetically: this.refs.showTagsAlphabetically.checked,
+        saveTagsAlphabetically: this.refs.saveTagsAlphabetically.checked,
         enableLiveNoteCounts: this.refs.enableLiveNoteCounts.checked,
         disableDirectWrite: this.refs.uiD2w != null
           ? this.refs.uiD2w.checked
@@ -244,6 +245,17 @@ class UiTab extends React.Component {
           }
           <div styleName='group-header2'>Tags</div>
 
+          <div styleName='group-checkBoxSection'>
+            <label>
+              <input onChange={(e) => this.handleUIChange(e)}
+                checked={this.state.config.ui.saveTagsAlphabetically}
+                ref='saveTagsAlphabetically'
+                type='checkbox'
+              />&nbsp;
+              {i18n.__('Save tags of a note in alphabetical order')}
+            </label>
+          </div>
+          
           <div styleName='group-checkBoxSection'>
             <label>
               <input onChange={(e) => this.handleUIChange(e)}