Removed syntastic and replaced it with ale

Read more here:
https://github.com/w0rp/ale

sources_non_forked/ale/ale_linters/handlebars/embertemplatelint.vim

@@ -0,0 +1,48 @@
+" Author: Adrian Zalewski <aazalewski@hotmail.com>
+" Description: Ember-template-lint for checking Handlebars files
+
+call ale#Set('handlebars_embertemplatelint_executable', 'ember-template-lint')
+call ale#Set('handlebars_embertemplatelint_use_global', 0)
+
+function! ale_linters#handlebars#embertemplatelint#GetExecutable(buffer) abort
+    return ale#node#FindExecutable(a:buffer, 'handlebars_embertemplatelint', [
+    \   'node_modules/.bin/ember-template-lint',
+    \])
+endfunction
+
+function! ale_linters#handlebars#embertemplatelint#GetCommand(buffer) abort
+    return ale_linters#handlebars#embertemplatelint#GetExecutable(a:buffer)
+    \   . ' --json %t'
+endfunction
+
+function! ale_linters#handlebars#embertemplatelint#Handle(buffer, lines) abort
+    let l:output = []
+    let l:json = ale#util#FuzzyJSONDecode(a:lines, {})
+
+    for l:error in get(values(l:json), 0, [])
+        if has_key(l:error, 'fatal')
+            call add(l:output, {
+            \   'lnum': get(l:error, 'line', 1),
+            \   'col': get(l:error, 'column', 1),
+            \   'text': l:error.message,
+            \   'type': l:error.severity == 1 ? 'W' : 'E',
+            \})
+        else
+            call add(l:output, {
+            \   'lnum': l:error.line,
+            \   'col': l:error.column,
+            \   'text': l:error.rule . ': ' . l:error.message,
+            \   'type': l:error.severity == 1 ? 'W' : 'E',
+            \})
+        endif
+    endfor
+
+    return l:output
+endfunction
+
+call ale#linter#Define('handlebars', {
+\   'name': 'ember-template-lint',
+\   'executable_callback': 'ale_linters#handlebars#embertemplatelint#GetExecutable',
+\   'command_callback': 'ale_linters#handlebars#embertemplatelint#GetCommand',
+\   'callback': 'ale_linters#handlebars#embertemplatelint#Handle',
+\})