Flatten API (#274)

Re-exports types from the toplevel instead of placing them in individual
modules (often which only contain one type).

This makes the API easier for users to navigate, while still retaining
the same module structure internally.

Additionally, this commit uses the `uuid` crate for modeling UUIDs.

src/msroots.rs

@@ -1,11 +1,4 @@
-//! `msroots`: PKCS#7 formatted certificate store for enterprise trusted roots.
-//!
-//! This `msroots` file contains a bag of certificates with empty content and
-//! an empty signature, allowing an enterprise root certificate truststore to
-//! be written to and read from a YubiKey.
-//!
-//! For more information, see:
-//! <https://docs.microsoft.com/en-us/windows-hardware/drivers/smartcard/developer-guidelines#-interoperability-with-msroots>
+//! PKCS#7 formatted certificate store for enterprise trusted roots.
 
 // Adapted from yubico-piv-tool:
 // <https://github.com/Yubico/yubico-piv-tool/>
@@ -53,7 +46,15 @@ const OBJ_MSROOTS5: u32 = 0x005f_ff15;
 const TAG_MSROOTS_END: u8 = 0x82;
 const TAG_MSROOTS_MID: u8 = 0x83;
 
-/// `msroots` file: PKCS#7-formatted certificate store for enterprise trust roots
+/// PKCS#7-formatted certificate store for enterprise trust roots.
+///
+/// The `msroots` file contains a bag of certificates with empty content and
+/// an empty signature, allowing an enterprise root certificate truststore to
+/// be written to and read from a YubiKey.
+///
+/// For more information, see:
+/// <https://docs.microsoft.com/en-us/windows-hardware/drivers/smartcard/developer-guidelines#-interoperability-with-msroots>
+#[cfg_attr(docsrs, doc(cfg(feature = "untested")))]
 pub struct MsRoots(Vec<u8>);
 
 impl MsRoots {