Adds ccache to jenkins slaves.

Creates symlinks in /usr/local/bin to automatically use ccache
and also fix some spacing issues. Symlink files depend on ccache
to prevent dangling links.

Addresses bug 989724.

Change-Id: I889ef377efd9a512dfec78c3c417931a764e514c

modules/jenkins_slave/manifests/init.pp

@@ -24,6 +24,7 @@ class jenkins_slave($ssh_key) {
                  "autoconf",
                  "automake",
                  "build-essential",
+                 "ccache",
                  "cdbs",
                  "curl",
                  "debootstrap",
@@ -121,4 +122,32 @@ class jenkins_slave($ssh_key) {
       force => true,
     }
 
+    file { 'ccachegcc':
+      name => '/usr/local/bin/gcc',
+      ensure => link,
+      target => '/usr/bin/ccache',
+      require => Package['ccache'],
+    }
+
+    file { 'ccacheg++':
+      name => '/usr/local/bin/g++',
+      ensure => link,
+      target => '/usr/bin/ccache',
+      require => Package['ccache'],
+    }
+
+    file { 'ccachecc':
+      name => '/usr/local/bin/cc',
+      ensure => link,
+      target => '/usr/bin/ccache',
+      require => Package['ccache'],
+    }
+
+    file { 'ccachec++':
+      name => '/usr/local/bin/c++',
+      ensure => link,
+      target => '/usr/bin/ccache',
+      require => Package['ccache'],
+    }
+
 }