Remove unused code from the addr module. (#50)

This PR removes some code leftover from rpki-rs.

Author: partim

src/addr.rs

@@ -233,10 +233,8 @@ impl<'a> arbitrary::Arbitrary<'a> for FamilyAndLen {
 /// - Other than that, prefixes are sorted numerically from low to high
 ///
 /// The rationale behind this ordering is that in most use cases processing a
-/// more-specific before any less-specific is more efficient (i.e. longest
-/// prefix matching in routing/forwarding)) or preventing unwanted
-/// intermediate stage (i.e. ROAs/VRPs for less-specifics making
-/// not-yet-processed more-specifics Invalid).
+/// more-specific before any less-specific is more efficient or preventing
+/// unwanted intermediate stage when evaluating prefixes in order.
 #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
 pub struct Prefix {
     /// The address family and prefix length all in one.
@@ -447,26 +445,6 @@ impl Ord for Prefix {
     }
 }
 
-//--- From
-
-#[cfg(feature = "repository")]
-impl From<crate::repository::roa::FriendlyRoaIpAddress> for Prefix {
-    fn from(addr: crate::repository::roa::FriendlyRoaIpAddress) -> Self {
-        Prefix::new(
-            addr.address(), addr.address_length()
-        ).expect("ROA IP address with illegal prefix length")
-    }
-}
-
-#[cfg(feature = "repository")]
-impl From<Prefix> for crate::repository::resources::IpBlock {
-    fn from(src: Prefix) -> Self {
-        crate::repository::resources::Prefix::new(
-            src.addr(), src.len()
-        ).into()
-    }
-}
-
 
 //--- Deserialize and Serialize
 
@@ -560,18 +538,20 @@ impl<'a> arbitrary::Arbitrary<'a> for Prefix {
 /// The pair of a prefix and an optional max-len.
 ///
 /// # Ordering
+///
 /// The ordering of MaxLenPrefixes is similar to the [ordering of
 /// Prefixes](Prefix#Ordering). The only difference is the optional MaxLen.
 /// When two prefixes are equal but differ in (presence of) max_len, the order
 /// is as follows:
-/// - any max_len always comes before no max_len
-/// - a larger (higher) max_len comes before a smaller (lower) max_len (e.g.
-/// 24 comes before 20). This is analog to how more-specifics come before
-/// less-specifics.
+///
+/// * any max_len always comes before no max_len
+/// * a larger (higher) max_len comes before a smaller (lower) max_len (e.g.
+///   24 comes before 20). This is analog to how more-specifics come before
+///   less-specifics.
 ///
 /// Note that the max_len can either be equal to the prefix length (with no
 /// practical difference from an omitted max_len) or larger than the prefix
-/// length. The max_len can not be smaller than the prefix length. Because of
+/// length. The max_len cannot be smaller than the prefix length. Because of
 /// that, we can safely order 'any max_len' before 'no max_len' for equal
 /// prefixes.
 #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]