Significant changes

• FlexASIO now accepts any sample rate and channel count in WASAPI Shared mode. See #32.
  • This fixes a long-standing annoyance with WASAPI Shared.
  • This is done by instructing WASAPI to convert the sample rate and channel count internally, just like DirectSound and MME already do.
  • This new behaviour is enabled by default but can be disabled using the wasapiAutoConvert option.

Minor changes

• Fix issue where FlexASIO would crash applications that already link with PortAudio directly (e.g. Polyphone). See #47.
• Fix issue with FlexASIOTest being unable to read 24-bit files. See #42.