This was found to cause a quality regression (e.g. in the velvet sample)

Tuned the tonality estimator to trigger on signals where only part of the
spectrum is tonal. Also tuned the pitch detector not to be confused
by short-term correlation.

- New DC rejection filter that avoids numerical issues
- Higher cap on HF dynalloc
- Proper filter memory for transient detector
- Prevents transient detector from detecting low-freq tones as transients

Fixes two leakage problems on the wood blocks sample
- Removes DC which causes leakage with no masking
- Detect leakage by comparing short-MDCT energy to long-MDCT energy
  and boost allocation for bands with leakage

Haven't tested it much and not sure not to use it without risk
for high-quality streams that may change bandwidth

Also, reducing the VBR rate on panned mono

Should be mostly usable now.

Conflicts:

	src/opus_encoder.c

Unlike the other headers, opus_multistream.h didn't declare
itself to be C code, causing confusing errors when the caller
tries to use the functions from C++.

Gregory Maxwell authored 12 years ago and Jean-Marc Valin committed 12 years ago

On MacOS, stdlib.h ends up including sys/signal.h, generating
warnings about the local variables called 'signal' shadowing
the global symbol signal(3).

This was originally done in 86476906 but it missed some use
of 'signal' in prototypes in headers where it didn't cause
warnings. Later the prototypes were moved around and the
warnings came back.

This also cleans up some cases in where stdlib.h was used
but shouldn't be required.

Both are still built and installed by default though.

Instead of just its build stamp :)

As best we recall, this was used to version the
library filename during rapid development. It's
no longer needed now that the bitstream is frozen
and isn't hooked up to anything in the build system.

The config.h version defines were declared in the
middle of the math feature testing. This commit moves
it to the top of configure.ac where the other version
number code resides.

Conflicts:
	README

This reverts commit 9f407afa.