Use compose-spec parser

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>

vendor/github.com/imdario/mergo/.travis.yml

@@ -1,4 +1,7 @@
 language: go
+arch:
+    - amd64
+    - ppc64le
 install:
   - go get -t
   - go get golang.org/x/tools/cmd/cover

vendor/github.com/imdario/mergo/README.md

@@ -97,7 +97,7 @@ If Mergo is useful to you, consider buying me a coffee, a beer, or making a mont
 - [mantasmatelis/whooplist-server](https://github.com/mantasmatelis/whooplist-server)
 - [jnuthong/item_search](https://github.com/jnuthong/item_search)
 - [bukalapak/snowboard](https://github.com/bukalapak/snowboard)
-- [janoszen/containerssh](https://github.com/janoszen/containerssh)
+- [containerssh/containerssh](https://github.com/containerssh/containerssh)
 
 ## Install
 

vendor/github.com/imdario/mergo/merge.go

@@ -95,13 +95,18 @@ func deepMerge(dst, src reflect.Value, visited map[uintptr]*visit, depth int, co
 				}
 			}
 		} else {
-			if (isReflectNil(dst) || overwrite) && (!isEmptyValue(src) || overwriteWithEmptySrc) {
+			if dst.CanSet() && (isReflectNil(dst) || overwrite) && (!isEmptyValue(src) || overwriteWithEmptySrc) {
 				dst.Set(src)
 			}
 		}
 	case reflect.Map:
 		if dst.IsNil() && !src.IsNil() {
-			dst.Set(reflect.MakeMap(dst.Type()))
+			if dst.CanSet() {
+				dst.Set(reflect.MakeMap(dst.Type()))
+			} else {
+				dst = src
+				return
+			}
 		}
 
 		if src.Kind() != reflect.Map {