added filenames_map.go generation

languagesByFilename now is a map[string]string

internal/code-generator/generator/test_files/filenames.gold

@@ -0,0 +1,12 @@
+package slinguist
+
+// CODE GENERATED AUTOMATICALLY WITH gopkg.in/src-d/simple-linguist.v1/internal/code-generator
+// THIS FILE SHOULD NOT BE EDITED BY HAND
+// Extracted from github/linguist commit: fe8b44ab8a225b1ffa75b983b916ea22fee5b6f7
+
+var languagesByFilename = map[string]string{
+	"APKBUILD":       "Alpine Abuild",
+	"CMakeLists.txt": "CMake",
+	"Cakefile":       "CoffeeScript",
+	"mix.lock":       "Elixir",
+}

internal/code-generator/generator/test_files/filenames.test.go.tmpl

@@ -0,0 +1,11 @@
+package slinguist
+
+// CODE GENERATED AUTOMATICALLY WITH gopkg.in/src-d/simple-linguist.v1/internal/code-generator
+// THIS FILE SHOULD NOT BE EDITED BY HAND
+// Extracted from github/linguist commit: {{ getCommit }}
+
+var languagesByFilename = map[string]string{
+	{{range $filename, $language := . -}}
+	"{{ $filename }}":	{{- printf "%q" $language -}},
+	{{end -}}
+}

internal/code-generator/generator/test_files/filenames.test.yml

@@ -0,0 +1,13 @@
+---
+Alpine Abuild:
+  filenames:
+  - APKBUILD
+CMake:
+  filenames:
+  - CMakeLists.txt
+CoffeeScript:
+  filenames:
+  - Cakefile
+Elixir:
+  filenames:
+  - mix.lock