docs: Make a slightly better comment for *Properties::duration

Author: Serial-ATA

src/aac/properties.rs

@@ -37,7 +37,7 @@ impl AACProperties {
 		self.audio_object_type
 	}
 
-	/// Duration
+	/// Duration of the audio
 	pub fn duration(&self) -> Duration {
 		self.duration
 	}

src/ape/properties.rs

@@ -35,7 +35,7 @@ impl From<ApeProperties> for FileProperties {
 }
 
 impl ApeProperties {
-	/// Duration
+	/// Duration of the audio
 	pub fn duration(&self) -> Duration {
 		self.duration
 	}

src/iff/wav/properties.rs

@@ -52,7 +52,7 @@ impl From<WavProperties> for FileProperties {
 }
 
 impl WavProperties {
-	/// Duration
+	/// Duration of the audio
 	pub fn duration(&self) -> Duration {
 		self.duration
 	}

src/mp4/properties.rs

@@ -166,7 +166,7 @@ impl From<Mp4Properties> for FileProperties {
 }
 
 impl Mp4Properties {
-	/// Duration
+	/// Duration of the audio
 	pub fn duration(&self) -> Duration {
 		self.duration
 	}

src/mpeg/properties.rs

@@ -40,7 +40,7 @@ impl From<MPEGProperties> for FileProperties {
 }
 
 impl MPEGProperties {
-	/// Duration
+	/// Duration of the audio
 	pub fn duration(&self) -> Duration {
 		self.duration
 	}

src/ogg/opus/properties.rs

@@ -35,7 +35,7 @@ impl From<OpusProperties> for FileProperties {
 }
 
 impl OpusProperties {
-	/// Duration
+	/// Duration of the audio
 	pub fn duration(&self) -> Duration {
 		self.duration
 	}

src/ogg/speex/properties.rs

@@ -38,7 +38,7 @@ impl From<SpeexProperties> for FileProperties {
 }
 
 impl SpeexProperties {
-	/// Duration
+	/// Duration of the audio
 	pub fn duration(&self) -> Duration {
 		self.duration
 	}

src/ogg/vorbis/properties.rs

@@ -37,7 +37,7 @@ impl From<VorbisProperties> for FileProperties {
 }
 
 impl VorbisProperties {
-	/// Duration
+	/// Duration of the audio
 	pub fn duration(&self) -> Duration {
 		self.duration
 	}

src/properties.rs

@@ -45,7 +45,7 @@ impl FileProperties {
 		}
 	}
 
-	/// Duration
+	/// Duration of the audio
 	pub fn duration(&self) -> Duration {
 		self.duration
 	}

src/wavpack/properties.rs

@@ -36,7 +36,7 @@ impl From<WavPackProperties> for FileProperties {
 }
 
 impl WavPackProperties {
-	/// Duration
+	/// Duration of the audio
 	pub fn duration(&self) -> Duration {
 		self.duration
 	}