Add Result alias (#271)

Adds a `yubikey::Result` alias with `yubikey::Error` as the error type.

Since we only have one `Error` type, this simplifies the return types
where a `Result` is returned.

cli/src/commands.rs

@@ -36,7 +36,7 @@ pub struct YubiKeyCli {
 
 impl YubiKeyCli {
     /// Print usage information
-    pub fn print_usage() -> Result<(), io::Error> {
+    pub fn print_usage() -> io::Result<()> {
         let mut stdout = STDOUT.lock();
         stdout.reset()?;
 

cli/src/commands/readers.rs

@@ -53,7 +53,7 @@ impl ReadersCmd {
         index: usize,
         name: &str,
         serial: Serial,
-    ) -> Result<(), io::Error> {
+    ) -> io::Result<()> {
         stream.set_color(ColorSpec::new().set_bold(true))?;
         write!(stream, "{:>3}:", index)?;
         stream.reset()?;

cli/src/commands/status.rs

@@ -51,7 +51,7 @@ impl StatusCmd {
         stream: &mut StandardStreamLock<'_>,
         name: &str,
         value: impl ToString,
-    ) -> Result<(), io::Error> {
+    ) -> io::Result<()> {
         stream.set_color(ColorSpec::new().set_bold(true))?;
         write!(stream, "{:>12}:", name)?;
         stream.reset()?;

cli/src/lib.rs

@@ -27,7 +27,7 @@ pub fn print_cert_info(
     yubikey: &mut YubiKey,
     slot: SlotId,
     stream: &mut StandardStreamLock<'_>,
-) -> Result<(), io::Error> {
+) -> io::Result<()> {
     let cert = match Certificate::read(yubikey, slot) {
         Ok(c) => c,
         Err(e) => {
@@ -82,7 +82,7 @@ fn print_cert_attr(
     stream: &mut StandardStreamLock<'_>,
     name: &str,
     value: impl ToString,
-) -> Result<(), io::Error> {
+) -> io::Result<()> {
     stream.set_color(ColorSpec::new().set_bold(true))?;
     write!(stream, "{:>12}:", name)?;
     stream.reset()?;

cli/src/terminal.rs

@@ -143,7 +143,7 @@ impl Status {
     }
 
     /// Print the given message
-    fn print(self, stream: &StandardStream, msg: impl AsRef<str>) -> Result<(), io::Error> {
+    fn print(self, stream: &StandardStream, msg: impl AsRef<str>) -> io::Result<()> {
         let mut s = stream.lock();
         s.reset()?;
         s.set_color(ColorSpec::new().set_fg(self.color).set_bold(self.bold))?;