update Rakefile

Rakefile

@@ -1,18 +1,34 @@
 require 'rake/clean'
+require 'rake/contrib/sys'
 
 SRC = FileList['lib/*']
 CLEAN.include('doc/*')
 CLEAN.include('ndoc')
 
+desc 'Create documentation'
 file 'doc' => SRC do
   sh "phpdoc --sourcecode on -t `pwd`/doc -d `pwd`/lib -ti 'trails documentation' -o 'HTML:frames:earthli'"
 end
 
+desc 'Run all unit tests'
 task 'test' do
   sh "php test/all_tests.php"
 end
 
-task 'shrink' do
-  sh "php lib/src/trails.php > lib/trails-unabridged.php"
+desc 'Build release'
+task 'build' => 'compile' do
   sh "php tools/shrink.php lib/trails-unabridged.php > lib/trails.php"
+  sh "wc lib/trails.php"
+end
+
+desc 'Compile release'
+task 'compile' do
+  sh "php lib/src/trails.php > lib/trails-unabridged.php"
+end
+
+desc 'Run coverage'
+task 'coverage' do
+  Sys.indir "test" do
+    sh "php coverage.php"
+  end
 end