Added ToC to usage page
diff --git a/src/site/markdown/usage.md b/src/site/markdown/usage.md
index 3150ab9..88da55d 100644
--- a/src/site/markdown/usage.md
+++ b/src/site/markdown/usage.md
@@ -20,14 +20,16 @@
See the License for the specific language governing permissions and
limitations under the License.
-->
-## Loggers<span id="anchor"></span>
+[TOC]
+
+# Loggers {#loggers}
Log4cxx has three main components: *loggers*, *appenders* and *layouts*.
These three types of components work together to enable developers to
log messages according to message type and level, and to control at
runtime how these messages are formatted and where they are reported.
-### Hierarchy<span id="anchor-1"></span>
+## Hierarchy {#hierarchy}
The first and foremost advantage of any logging API over plain
`std::cout` resides in its ability to disable certain log statements
@@ -87,7 +89,7 @@
#define LOG4CXX_FATAL(logger, expression) ...
~~~
-### Levels<span id="anchor-2"></span>
+## Levels {#levels}
Loggers *may* be assigned levels. The pre-defined levels: TRACE, DEBUG,
INFO, WARN, ERROR and FATAL are defined in the
@@ -160,7 +162,7 @@
their level value from their nearest parent *X* having an assigned
level.
-### Requests<span id="anchor-3"></span>
+## Requests {#requests}
Logging requests are made by invoking a method of a logger instance,
preferrably through the use of LOG4CXX\_INFO or similar macros which
@@ -259,7 +261,7 @@
Nevertheless, naming loggers after the class where they are located
seems to be the best strategy known so far.
-## Appenders and Layouts<span id="anchor-4"></span>
+# Appenders and Layouts {#appenders-and-layouts}
The ability to selectively enable or disable logging requests based on
their logger is only part of the picture. Log4cxx allows logging
@@ -338,7 +340,7 @@
name of the logger associated with the log request. The text after the
'-' is the message of the statement.
-## Configuration<span id="anchor-5"></span>
+# Configuration {#configuration}
Inserting log requests into the application code requires a fair amount
of planning and effort. Observation shows that approximately 4 percent
@@ -590,7 +592,7 @@
according to local server policy, for example by forwarding the log
event to a second log4cxx server.
-## Default Initialization Procedure<span id="anchor-6"></span>
+# Default Initialization Procedure {#default-initialization-procedure}
The log4cxx library does not make any assumptions about its environment.
In particular, there are no default log4cxx appenders. Under certain
@@ -615,7 +617,7 @@
contain a fully qualified class name of a class that implements the
Configurator interface.
-## Nested Diagnostic Contexts<span id="anchor-7"></span>
+# Nested Diagnostic Contexts {#nested-diagnostic-contexts}
Most real-world systems have to deal with multiple clients
simultaneously. In a typical multithreaded implementation of such a
@@ -683,7 +685,7 @@
allows each virtual host to possess its own copy of the logger
hierarchy.
-## Performance<span id="anchor-8"></span>
+# Performance {#performance}
One of the often-cited arguments against logging is its computational
cost. This is a legitimate concern as even moderately sized applications
@@ -728,7 +730,7 @@
layouts (formatters) perform as quickly as possible. The same is
true for appenders.
-## Conclusions<span id="anchor-9"></span>
+# Conclusions {#conclusions}
Apache Log4cxx is a popular logging package written in C++. One of its
distinctive features is the notion of inheritance in loggers. Using a
