Haven 0.2.0

haven 0.2.0

• zap_labels() now leaves unlabelled vectors unchanged, making it easier
  to apply to all columns.
• write_dta() and write_sav() take more care to always write output as
  UTF-8 (#36)
• write_dta() and write_sav() won't crash if you give them invalid paths,
  and you can now use ~ to refer to your home directory (#37).
• Byte variables are now correctly read into integers (not strings, #45),
  and missing values are captured correctly (#43).
• Added read_stata() as alias to read_dta() (#52).
• read_spss() uses extension to automatically choose between read_sav()
  and read_por() (#53)
• Updates from ReadStat. Including fixes for various parsing bugs, more
  encodings, and better support for large files.
• hms objects deal better with missings when printing.
• Fixed bug causing labels for numeric variables to be read in as
  integers and associated error: Error: xandlabels must be same type