Add support for arbitary filename of Dockerfile in build command

[askoretskiy]

docker allows to build explicit filename:
-f, --file= Name of the Dockerfile (Default is 'PATH/Dockerfile')

docker build -f Dockerfile.test

However it is not possible with compose:

web:
build: Dockerfile.test

Result:

Traceback (most recent call last):
File "/usr/local/bin/docker-compose", line 8, in
load_entry_point('docker-compose==1.2.0', 'console_scripts', 'docker-compose')()
File "/Library/Python/2.7/site-packages/compose/cli/main.py", line 31, in main
command.sys_dispatch()
File "/Library/Python/2.7/site-packages/compose/cli/docopt_command.py", line 21, in sys_dispatch
self.dispatch(sys.argv[1:], None)
File "/Library/Python/2.7/site-packages/compose/cli/command.py", line 27, in dispatch
super(Command, self).dispatch(_args, *_kwargs)
File "/Library/Python/2.7/site-packages/compose/cli/docopt_command.py", line 24, in dispatch
self.perform_command(*self.parse(argv, global_options))
File "/Library/Python/2.7/site-packages/compose/cli/command.py", line 59, in perform_command
handler(project, command_options)
File "/Library/Python/2.7/site-packages/compose/cli/main.py", line 119, in build
project.build(service_names=options['SERVICE'], no_cache=no_cache)
File "/Library/Python/2.7/site-packages/compose/project.py", line 191, in build
service.build(no_cache)
File "/Library/Python/2.7/site-packages/compose/service.py", line 475, in build
nocache=no_cache,
File "/Library/Python/2.7/site-packages/docker/client.py", line 319, in build
raise TypeError("You must specify a directory to build in path")
TypeError: You must specify a directory to build in path

[aanand]

Implemented in #1075 - just waiting on a release.

[askoretskiy]

Thanks! That's exactly what I need. Any idea on release date?