The base class completer Inner chose the first filetype available and
would use the triggers for it.
The triggers are now chosen considering the first for the current buffer
that is supported by the current completer. If there is no intersection,
it fallsback to considering the first filetype for the buffer.
This provides a framework for completer-writers to create
completer-specific commands. I have in mind to use this for the clang
completer to force reloading of a flags module via `:YcmCompleter reload`.
Now there's a nice user-configurable setting for when YCM should trigger
semantic completion. This is very useful for the new omni_completer that uses
data coming from Vim's omnicomplete system.
This was intended to show the full clang output for a given diagnostic,
including notes. But it appears that libclang does not provide this
functionality...
