[opus] SPEEX and OPUS questions and minor issues

[dos386]

I recently stumbled upon <speex/speex_resampler.h> and made a chain of
discoveries:

- "http://speex.org/downloads" some links are broken ("rarewares" and git)

- there is some (minor) development (whitespace and more) of the "dead" Speex
codec ... will there be a release? (I don't really need such myself)

- there is some (more useful?) development of the "Speex DSP" part
split off in 2009 ... will there be a release? Maybe the page should
document the Speex codec is deprecated but "Speex DSP" is not? Maybe
"Speex DSP" could have a better "home" than in "shadow" of the dead
Speex codec?

- documentation of "Speex DSP" ... the latest release
"speexdsp-1.2rc3.tar.gz" from 2015 still contains "The Speex Codec
Manual Version 1.2 Beta 3" from 2007 ... it documents the codec part,
not the DSP part ... maybe the documentation should be updated and
split off too?

- file "resample.c"
- - note "This resampler is relatively new" maybe no longer true
- - link "http://www-ccrma.stanford.edu/~jos/resample" broken (delete "www-")
- - is "FIXED_POINT" supposed to work? There seems to be some "semi-translated"
code ...

- the resample code from "Speex DSP" is used in OPUS TOOLS ...version
0.1.9 from 2014 contains an outdated version of the resampling code
from 2009 with minimal modifications ... maybe it should be
synchronized with the code inside "Speex DSP"?