Fix broken links in documentation.

Alexandre Dutra · Alexandre Dutra · commit 4adddcfda90c · 2015-07-28T11:52:08.000+02:00
diff --git a/features/custom_codecs/README.md b/features/custom_codecs/README.md
@@ -303,7 +303,7 @@ serializing and deserializing. It's possible to bypass this step with a
 lower-level implementation that manipulates the binary stream directly.
 That's also how the object mapper handles UDTs, and you can rely on the
 mapper to generate UDT codecs for you; see
-[this page](object_mapper/custom_codecs/#implicit-udt-codecs) for more
+[this page](../object_mapper/custom_codecs/#implicit-udt-codecs) for more
 information.
 
 ### Limitations
@@ -377,7 +377,7 @@ A codec lookup operation may be costly; to mitigate this, the `CodecRegistry` ca
 
 The following situations are exceptions where it is not possible to cache lookup results:
 
-* With [SimpleStatement] and [BuiltStatement] (Query Builder) instances; in these places, the driver has
+* With [SimpleStatement] instances and [BuiltStatement] instances (created via the Query Builder); in these places, the driver has
   no way to determine the right CQL type to use, so it performs a best-effort heuristic to guess which codec to use.
 * When using "ambiguous" methods of `BoundStatement` and `Row`, such as [setList()][setList],
   [setSet()][setSet], [setMap()][setMap], [setObject()][setObject];
diff --git a/upgrade_guide/README.md b/upgrade_guide/README.md
@@ -11,7 +11,7 @@ It is **not binary compatible** with the driver's 2.1 branch.
 The main changes were introduced by the custom codecs feature (see below).
 We've also seized the opportunity to remove code that was deprecated in 2.1.
 
-1.  [Custom codecs](../features/custom_codecs/README.md)
+1.  [Custom codecs](../features/custom_codecs/)
     ([JAVA-721](https://datastax-oss.atlassian.net/browse/JAVA-721))
     introduce several breaking changes and also modify a few runtime behaviors.
 
@@ -249,7 +249,7 @@ Merged from 2.0.11:
 
 ### 2.1.6
 
-See [2.0.10](20x-to-2010).
+See [2.0.10](#2-0-x-to-2-0-10).
 
 
 ### 2.1.2
@@ -368,7 +368,7 @@ driver, but rather third-party frameworks and tools.
    If you know that the CQL functions or expressions are safe, use
    `setIdempotent(true)` on the statement.
 
-### 2.0.x to 2.0.10
+### <a name="2-0-x-to-2-0-10"></a>2.0.x to 2.0.10
 
 We try to avoid breaking changes within a branch (2.0.x to 2.0.y), but
 2.0.10 saw a lot of new features and internal improvements. There is one
