Remove sysdata.rda internals and replace with user-friendly files

[stufield]

• removing the internal sysdata.rda object and replacing those functions with actual R/*.R files
• there is no need to keep these internal functions hidden
• newly exported functions:
  • addAttributes()
  • addClass()
  • cleanNames()
  • getAdatVersion()
• new internal functions:
  • convertColMeta()
  • genRowNames()
  • syncColMeta()
  • parseCheck()
  • scaleAnalytes()
• Makefile no longer has recipe for generating sysdata.rda
• minor tweaks to some unit tests during porting over from internal code base
• fixes #59