Install FHS-style paths

--- a/conf/graphite.wsgi.example
+++ b/conf/graphite.wsgi.example
@@ -1,4 +1,4 @@
 import sys
-sys.path.append('/opt/graphite/webapp')
+sys.path.append('@GENTOO_PORTAGE_EPREFIX@/usr/share/graphite-web/webapp')
 
 from graphite.wsgi import application
--- a/webapp/graphite/local_settings.py.example
+++ b/webapp/graphite/local_settings.py.example
@@ -101,6 +101,7 @@
 # Change only GRAPHITE_ROOT if your install is merely shifted from /opt/graphite
 # to somewhere else
 #GRAPHITE_ROOT = '/opt/graphite'
+GRAPHITE_ROOT = '@GENTOO_PORTAGE_EPREFIX@/usr/share/graphite-web'
 
 # Most installs done outside of a separate tree such as /opt/graphite will
 # need to change these settings. Note that the default settings for each
@@ -110,6 +111,11 @@
 #STATIC_ROOT = '/opt/graphite/static'
 #LOG_DIR = '/opt/graphite/storage/log/webapp'
 #INDEX_FILE = '/opt/graphite/storage/index'     # Search index file
+CONF_DIR = '@GENTOO_PORTAGE_EPREFIX@/etc/graphite-web'
+STORAGE_DIR = '@GENTOO_PORTAGE_EPREFIX@/var/lib/carbon'
+STATIC_ROOT = '@GENTOO_PORTAGE_EPREFIX@/usr/share/graphite-web/webapp/content'
+LOG_DIR = '@GENTOO_PORTAGE_EPREFIX@/var/log/graphite-web'
+INDEX_FILE = '@GENTOO_PORTAGE_EPREFIX@/var/lib/graphite-web/index'  # Search index file
 
 # To further or fully customize the paths, modify the following. Note that the
 # default settings for each of these are relative to CONF_DIR and STORAGE_DIR
@@ -127,6 +133,8 @@
 #CERES_DIR = '/opt/graphite/storage/ceres'
 #WHISPER_DIR = '/opt/graphite/storage/whisper'
 #RRD_DIR = '/opt/graphite/storage/rrd'
+WHISPER_DIR = '@GENTOO_PORTAGE_EPREFIX@/var/lib/carbon/whisper'
+RRD_DIR = '@GENTOO_PORTAGE_EPREFIX@/var/lib/carbon/rrd'
 #
 # Data directories using the "Standard" metrics finder (i.e. not Ceres)
 #STANDARD_DIRS = [WHISPER_DIR, RRD_DIR] # Default: set from the above variables
@@ -244,7 +244,7 @@
 #
 #DATABASES = {
 #    'default': {
-#        'NAME': '/opt/graphite/storage/graphite.db',
+#        'NAME': '@GENTOO_PORTAGE_EPREFIX@/var/lib/graphite-web/graphite.db',
 #        'ENGINE': 'django.db.backends.sqlite3',
 #        'USER': '',
 #        'PASSWORD': '',
