feat(Models): Add German, Frent and English models (#214)

Added audio samples and keywords for the 3 new models:
```
de-DE_NarrowbandModel
fr-FR_NarrowbandModel
en-US_ShortForm_NarrowbandModel
```

Author: kkeerthana

public/audio/de-DE_NarrowbandModel_sample1.wav

@@ -13,6 +13,17 @@
     },
     "description": "French broadband model."
   },
+  {
+    "name": "fr-FR_NarrowbandModel", 
+    "language": "fr-FR", 
+    "url": "https://stream.watsonplatform.net/speech-to-text/api/v1/models/fr-FR_NarrowbandModel", 
+    "rate": 8000, 
+    "supported_features": {
+      "custom_language_model": true, 
+      "speaker_labels": true
+    }, 
+    "description": "French narrowband model."
+  },
   {
     "name": "en-US_NarrowbandModel",
     "language": "en-US",
@@ -188,5 +199,27 @@
       "speaker_labels": false
     },
     "description": "German broadband model."
+  },
+  {
+    "name": "de-DE_NarrowbandModel", 
+    "language": "de-DE", 
+    "url": "https://stream.watsonplatform.net/speech-to-text/api/v1/models/de-DE_NarrowbandModel", 
+    "rate": 8000, 
+    "supported_features": {
+      "custom_language_model": true, 
+      "speaker_labels": false
+    }, 
+    "description": "German narrowband model."
+  },
+  {
+    "name": "en-US_ShortForm_NarrowbandModel", 
+    "language": "en-US", 
+    "url": "https://stream.watsonplatform.net/speech-to-text/api/v1/models/en-US_ShortForm_NarrowbandModel", 
+    "rate": 8000, 
+    "supported_features": {
+      "custom_language_model": true, 
+      "speaker_labels": true
+    }, 
+    "description": "US English Short Form narrowband model."
   }
 ]

public/audio/de-DE_NarrowbandModel_sample2.wav

@@ -47,6 +47,18 @@
       "speaker_labels": true
     }
   ],
+  "en-US_ShortForm_NarrowbandModel": [
+    {
+      "filename": "english2.g712.wav",
+      "keywords": "twenty thousand dollars, filled out, car",
+      "speaker_labels": true
+    },
+    {
+      "filename": "english3.g712.wav",
+      "keywords": "new company, client, Chris",
+      "speaker_labels": true
+    }
+  ],
   "en-US_NarrowbandModel": [
     {
       "filename": "english2.g712.wav",
@@ -183,6 +195,18 @@
       "speaker_labels": false
     }
   ],
+  "de-DE_NarrowbandModel": [
+    {
+      "filename": "de-DE_NarrowbandModel_sample1.wav",
+      "keywords": "Augen, Lindenbäumen, Türme von Wien",
+      "speaker_labels": false
+    },
+    {
+      "filename": "de-DE_NarrowbandModel_sample2.wav",
+      "keywords": "Geige, mein Vater, Dorf",
+      "speaker_labels": false
+    }
+  ],
   "pt-BR_BroadbandModel": [
     {
       "filename": "pt-BR_Sample1-16KHz.wav",
@@ -242,5 +266,17 @@
       "keywords": "conscience, esprit de fraternité, libres",
       "speaker_labels": false
     }
+  ],
+  "fr-FR_NarrowbandModel": [
+    {
+      "filename": "fr-FR_Narrowband_sample1.wav",
+      "keywords": "durée du travail, loisirs",
+      "speaker_labels": true
+    },
+    {
+      "filename": "fr-FR_Narrowband_sample2.wav",
+      "keywords": "conscience, esprit de fraternité, libres",
+      "speaker_labels": true
+    }
   ]
 }