Updates to reflect recent changes in hydrogenaudio wiki.
Improved detection of MPEG audio data in RIFF WAVE files.
see tracker item 3545112: Invalid sampling detection
+ new command line option "--gain x",  more convenient to adjust replay gain, just use whatever decibel value LAME reported before.
+ out-dir option mentioned in long help text
- code refactorings
- changed "mask adding", get the max of 3 different ones
ignore developer-only switches, but parse them for command line compatibility reasons
trying to improve strong tonal samples (lead-voice.wav)
bump version
fix for tracker item ID 3558466: Bug in path handling
fix for tracker item 3567844: problem with Tag genre
fix for tracker item 3565659: no progress indication with pipe input :(
fix for tracker item 3544957: scale (empty) silent encode without warning

switches with missing argument values will be ignored.  (Those with integer or floating point values, at least)
fix for tracker item 3580176: environment variable LAMEOPT doesn't work anymore