Changes for Csound 7

Here is a list of ideas that should be changed in Csound 7

• Do careful benchamrking and analysis of performance code to find bottlenecks, unnecessary/obsolete code and other small things which could contribute to speedup
• Do a full audit of the CSOUND struct to:
  • Homogenize names
  • Purge unused members
  • Move opcode specific members out of the CSOUND struct and into global variables
  • Remove obsolete, unnecessary members, like initonly flag (to process with init pass only).
• Remove API function csoundYield(csound), as well as the CsoundYieldCallback and Callback setter. The API members: csound->evt_poll_cnt and csound->evt_poll_maxcnt are no longer needed.
• Cleanup directory structure and remove unused/obsolete/unnecessary files
• Do an audit of command line flags and removed unnecessary/obsolete ones
• Consider writing some ugens using vectorized operations for efficiency.