Issue #767: add initial support for Chuvash language

CHANGELOG.md

 
 new languages:
 *  chr (Cherokee) -- Michael Conrad
+*  cu (Chuvash) -- boracasli98, Valdis Vitolins
 *  haw (Hawaiian) -- Valdis Vitolins
 *  he (Hebrew) -- boracasli98, Valdis Vitolins
 *  ltg (Latgalian) -- Valdis Vitolins

Makefile.am

 	espeak-ng-data/ca_dict \
 	espeak-ng-data/chr_dict \
 	espeak-ng-data/cs_dict \
+	espeak-ng-data/cv_dict \
 	espeak-ng-data/cy_dict \
 	espeak-ng-data/da_dict \
 	espeak-ng-data/de_dict \
 cs: espeak-ng-data/cs_dict
 espeak-ng-data/cs_dict: dictsource/cs_list dictsource/cs_rules dictsource/cs_extra dictsource/cs_emoji
 
+cv: espeak-ng-data/cv_dict
+espeak-ng-data/cv_dict: dictsource/cv_list dictsource/cv_rules dictsource/cv_extra
+
 cy: espeak-ng-data/cy_dict
 espeak-ng-data/cy_dict: dictsource/cy_list dictsource/cy_rules dictsource/cy_extra dictsource/cy_emoji
 
 espeak-ng-data/te_dict: dictsource/te_list dictsource/te_rules dictsource/te_extra dictsource/te_emoji
 
 tk: espeak-ng-data/tk_dict
-espeak-ng-data/tk_dict: dictsource/tk_list dictsource/tk_rules dictsource/tk_extra
+espeak-ng-data/tk_dict: dictsource/tk_list dictsource/tk_listx dictsource/tk_rules dictsource/tk_extra
 
 tn: espeak-ng-data/tn_dict
 espeak-ng-data/tn_dict: dictsource/tn_list dictsource/tn_rules dictsource/tn_extra

dictsource/cv_rules

+// This file is UTF8 encoded
+// Spelling-to-phoneme rules for Chuvash
+
+.group а
+        а        a
+
+.group ӑ
+        ӑ        @
+
+.group б
+        б        b
+
+.group в
+        в        v
+
+.group г
+        г        g
+
+.group д
+        д        d
+
+.group е
+     _) е        je
+        е        E
+
+.group ё
+        ё        jo
+
+.group ӗ
+        ӗ        8
+
+.group ж
+        ж        Z
+
+.group з
+        з        z
+
+.group и
+        и        i
+
+.group й
+        й        j
+
+.group к
+        к        k
+
+.group л
+        л        l
+
+.group м
+        м        m
+
+.group н
+        н        n
+
+.group о
+        о        o
+
+.group п
+        п        p
+
+.group р
+        р        R
+
+.group с
+        с        s
+
+.group ҫ
+        ҫ        C
+
+.group т
+        т        t
+        ть        t;
+
+.group у
+        у        u
+
+.group ӳ
+        ӳ        y
+
+.group ф
+        ф        f
+
+.group х
+        х        x
+
+.group ц
+        ц        ts
+
+.group ч
+        ч        tS
+
+.group ш
+        ш        S
+
+.group щ
+        щ        C:
+
+.group ъ
+        ъ        ?
+
+.group ы
+        ы        V
+
+.group ь
+        ь        ;
+
+.group э
+        э        e
+
+.group ю
+        ю        ju
+        
+.group я
+        я        ja 

docs/languages.md

 [private-use extensions](https://raw.githubusercontent.com/espeak-ng/bcp47-data/master/bcp47-extensions)
 have been used.
 
-The 118 supported languages and accents are:
+The 119 supported languages and accents are:
 
 | Family Code | Identifier        | Language Family       | Language                    | Accent/Dialect         |
 |-------------|-------------------|-----------------------|-----------------------------|------------------------|
 | `inc`       | `as`              | Indic                 | Assamese                    |                        |
 | `trk`       | `az`              | Turkic                | Azerbaijani                 |                        |
 | `trk`       | `ba`              |                       | Bashkir                     |                        |
+| `trk`       | `cu`              | Turkic                | Chuvash                     |                        |
 |             | `eu`              |                       | Basque                      |                        |
 | `inc`       | `bn`              | Indic                 | Bengali                     |                        |
 | `inc`       | `bpy`             | Indic                 | Bishnupriya Manipuri        |                        |

espeak-ng-data/lang/trk/cv

+name Chuvash
+language cv
+status testing

phsource/ph_chuvash

+phoneme V
+  vwl flag2 starttype #@ endtype #@
+  length 110
+  ipa ɯ
+  FMT(vowel/@_2)
+endphoneme
+
+phoneme 8
+  vwl starttype #@ endtype #@
+  length 100
+  IF thisPh(isWordEnd) THEN
+    length 140
+  ENDIF
+  FMT(vowel/8)
+endphoneme
+
+phoneme E
+  import_phoneme tr/E
+endphoneme
+
+phoneme y
+  import_phoneme tr/y
+endphoneme

phsource/phonemes

 phonemetable az tr
 include ph_azerbaijani
 
+phonemetable cv tr
+include ph_chuvash
+
 phonemetable tk tr
 include ph_turkmen