--log-level param in ti_args breaks the build about jast

[shodanuk]

Same goes for grunt dev -p android.

I've done a bit of digging and it appears that grunt-titanium doesn't actually merge in anything passed in the args param of the grunt task definition but simply concatenates it to the end of the generated ti command, resulting in duplicate --platform & --log-level params if they've been specified in ti_args.

The defaults in grunt-titanium only specify platform, log-level & projectDir, hence why the problem only exists for select params.

See https://github.com/tonylukasavage/grunt-titanium/blob/master/tasks/titanium.js#L157

A fairly simple fix for the platform param is to pass the grunt -p param into a new platform param in the grunt task definition.

Will put together a pull request in a sec.