Add HF Reference as a filter property
Make RefCount a non-integer type

It should only be accessed through the appropriate functions to ensure proper
atomicity.
Avoid freeing an in-use capture buffer

When stopping, ALSA may capture into its own storage buffer. Do not free
the storage buffer if it first reads from it.
Add a couple asserts to ensure a proper buffer

It should not be possible for a playing or paused source to not have a
valid buffer, but Clang's static analyzer doesn't know that. Hopefully
an assert will convince it.
Remove a dead assignment
Don't try to read the internal capture buffer into itself
Use an enum for the chorus and flanger waveforms
Initialize newformat to AL_NONE instead of a valid format
Initialize some variables when declaring them
Remove some unnecessary casts
Early-out when outN is 0
Don't bother stripping whitespace from comments
Initialize a pointer to NULL instead of a string
Ensure that LoopEnd > LoopStart

For the benefit of Clang's static analysis, which doesn't know that a
static source will always have a valid buffer and a buffer must have a
non-0 loop range.