Performance improvements / Remove unused stopword lists

* Plateforme de test: karukera
* 1er test : état actuel

```
2014-07-07 14:51:04,256 INFO  [jeeves.apphand] - NOTE: Using shapefile for spatial index, this can be slow for larger catalogs
2014-07-07 14:52:15,227 INFO  [jeeves.apphand] -   - Access manager...
71s d'initialisation de l'index
```

* 2ème test : suppression de listes de mots vides non utilisées (conservation des stopwords pour eng et fre)
```
2014-07-07 14:47:47,621 INFO  [jeeves.apphand] - NOTE: Using shapefile for spatial index, this can be slow for larger catalogs
2014-07-07 14:48:17,095 INFO  [jeeves.apphand] -   - Access manager...
30s
```

* Idem: 2nd répétition
```
2014-07-07 14:49:12,390 INFO  [jeeves.apphand] - NOTE: Using shapefile for spatial index, this can be slow for larger catalogs
2014-07-07 14:49:42,003 INFO  [jeeves.apphand] -   - Access manager...
30s
```

* 40 secondes de gain d'init au démarrage (par noeud)
* Memory:
 * All : Retained HEAP = 1835488
 * Only fre, eng : Retained HEAP = 275664