Fixes#486
This commit will add `dockerfilepath` key under Dockerstratergy in buildconfig.
dockerfilepath allow us to use dockerfiles which are named different than `Dockerfile` which are placed in context directory.
for example, for a docker-compose file:
```
version: "2"
services:
foo:
build:
context: "./build"
dockerfile: "Dockerfile-alternate"
command: "sleep 3600"
```
Resulting buildconfig will be:
```
apiVersion: v1
kind: BuildConfig
...
...
strategy:
dockerStrategy:
dockerfilePath: Dockerfile-alternate
type: Docker
...
...
```
Suraj Narwade
ec897ef50f