qdb: add missing configuration for Lang Belta and update documentation

CHANGELOG.md

 *  ltg (Latgalian) -- Valdis Vitolins
 *  nog (Nogai) -- boracasli98, Valdis Vitolins
 *  qu (Quechua) -- Valdis Vitolins
+*  qdb (Lang Belta) -- Da Def, Valdis Vitolins
 *  th (Thai) -- Valdis Vitolins
 *  tk (Turkmen) -- boracasli98, Valdis Vitolins
 *  ug (Uyghur) -- boracasli98, Valdis Vitolins

Makefile.am

 	phsource/ph_korean \
 	phsource/ph_kurdish \
 	phsource/ph_kyrgyz \
+	phsource/ph_langbelta \
 	phsource/ph_latin \
 	phsource/ph_latvian \
 	phsource/ph_lithuanian \
 	espeak-ng-data/pl_dict \
 	espeak-ng-data/pt_dict \
 	espeak-ng-data/py_dict \
+	espeak-ng-data/qdb_dict \
 	espeak-ng-data/qu_dict \
 	espeak-ng-data/quc_dict \
 	espeak-ng-data/ro_dict \
 py: espeak-ng-data/py_dict
 espeak-ng-data/py_dict: dictsource/py_list dictsource/py_rules dictsource/py_extra
 
+qdb: espeak-ng-data/qdb_dict
+espeak-ng-data/qdb_dict: dictsource/qdb_list dictsource/qdb_rules
+
 qu: espeak-ng-data/qu_dict
 espeak-ng-data/qu_dict: dictsource/qu_list dictsource/qu_rules dictsource/qu_extra
 

docs/languages.md

 # Languages
 
-Development version of eSpeak NG supports 121 languages and accents,
+Development version of eSpeak NG supports 122 languages and accents,
 which are listed in table below.
 
 To check, what languages are supported by distributed version, run `espeak-ng --voices` command.
 | `art`       | `py`              | Constructed           | Pyash                       |                        |
 | `zlw`       | `pl`              | West Slavic           | Polish                      |                        |
 | `roa`       | `pt-br`           | Romance               | Portuguese                  | Brazillian             |
+| `art`       | `qdb`             | Constructed           | Lang Belta                  |                        |
 |             | `qu`              |                       | Quechua                     |                        |
 | `myn`       | `quc`             | Mayan                 | K'iche'                     |                        |
 | `roa`       | `pt`              | Romance               | Portuguese                  | Portugal               |