Convert images to use .qrc file, move images

All images have been moved to the /img/ folder in order to fully
separate qml from images. The .qrc file allows qml to use the images by
appending the qrc:/ prefix before the abstract path to the image.

Note that the .qrc file is also check at compile time, which further
enhances the confidence the lack of errors.

Some of the images are not used in the QML, but instead directly passed
through to the OpenVR API. These have not been added to the .qrc file.

src/res/qml/RootPage.qml

@@ -344,7 +344,7 @@ MyStackViewPage {
                            Layout.leftMargin: 12
                            checkable: true
                            contentItem: Image {
-                               source: parent.checked ? "audio_page/mic_off.svg" : "audio_page/mic_on.svg"
+                               source: parent.checked ? "qrc:/microphone/off" : "qrc:/microphone/on"
                                sourceSize.width: 32
                                sourceSize.height: 32
                                anchors.fill: parent

src/res/qml/audio_page/device_selector/MicVolumeSlider.qml

@@ -61,7 +61,7 @@ ColumnLayout {
             Layout.leftMargin: 12
             checkable: true
             contentItem: Image {
-                source: parent.checked ? "../mic_off.svg" : "../mic_on.svg"
+                source: parent.checked ? "qrc:/microphone/off" : "qrc:/microphone/on"
                 sourceSize.width: 32
                 sourceSize.height: 32
                 anchors.fill: parent

src/res/qml/audio_page/device_selector/MirrorVolumeSlider.qml

@@ -62,7 +62,7 @@ ColumnLayout {
             Layout.leftMargin: 12
             checkable: true
             contentItem: Image {
-                source: parent.checked ? "../speaker_off.svg" : "../speaker_on.svg"
+                source: parent.checked ? "qrc:/speaker/off" : "qrc:/speaker/on"
                 sourceSize.width: 32
                 sourceSize.height: 32
                 anchors.fill: parent

src/res/qml/common/MyStackViewPage.qml

@@ -26,7 +26,7 @@ Rectangle {
                 enabled: headerShowBackButton
                 opacity: headerShowBackButton ? 1.0 : 0.0
                 contentItem: Image {
-                    source: "qrc:/common/back-arrow"
+                    source: "qrc:/common/backarrow"
                     sourceSize.width: 50
                     sourceSize.height: 50
                     anchors.fill: parent

src/res/qml/common/MyToggleButton.qml

@@ -31,7 +31,7 @@ CheckBox {
             height: 28
 			x: (parent.width - width) / 2
 			y: (parent.height - height) / 2
-            source: "qrc:/common/box-checkmark"
+            source: "qrc:/common/box_checkmark"
 			sourceSize.width: width
 			sourceSize.height: height
 			visible: parent.parent.checked

src/res/qml/utilities_page/media_keys/MediaControllerKeys.qml

@@ -25,10 +25,10 @@ GroupBox {
         }
 
         RowLayout {
-            property string playPauseButtonPath: "outline_play_pause_white_24dp.svg"
-            property string stopButtonPath: "outline_stop_white_24dp.svg"
-            property string previousButtonPath: "outline_skip_previous_white_24dp.svg"
-            property string nextButtonPath: "outline_skip_next_white_24dp.svg"
+            property string playPauseButtonPath: "qrc:/media_keys/play_pause"
+            property string stopButtonPath: "qrc:/media_keys/stop"
+            property string previousButtonPath: "qrc:/media_keys/previous"
+            property string nextButtonPath: "qrc:/media_keys/next"
 
             MediaButton {
                 id: previousSongButton

src/res/resources.qrc

@@ -1,6 +1,20 @@
 <!DOCTYPE RCC><RCC version="1.0">
 <qresource prefix="/common">
-    <file alias="back-arrow">img/common/backarrow.svg</file>
-    <file alias="box-checkmark">img/common/check.svg</file>
+    <file alias="backarrow">img/common/backarrow.svg</file>
+    <file alias="box_checkmark">img/common/check.svg</file>
+</qresource>
+<qresource prefix="/microphone">
+    <file alias="on">img/audio/microphone/mic_on.svg</file>
+    <file alias="off">img/audio/microphone/mic_off.svg</file>
+</qresource>
+<qresource prefix="/speaker">
+    <file alias="on">img/audio/speaker/speaker_on.svg</file>
+    <file alias="off">img/audio/speaker/speaker_off.svg</file>
+</qresource>
+<qresource prefix="/media_keys">
+    <file alias="play_pause">img/audio/media_keys/outline_play_pause_white_24dp.svg</file>
+    <file alias="next">img/audio/media_keys/outline_skip_next_white_24dp.svg</file>
+    <file alias="previous">img/audio/media_keys/outline_skip_previous_white_24dp.svg</file>
+    <file alias="stop">img/audio/media_keys/outline_stop_white_24dp.svg</file>
 </qresource>
 </RCC>