rerddap v0.3.4

MINOR IMPROVEMENTS

• Removed use of ncdf package, which has been taken off CRAN.
  Using ncdf4 now for all NetCDF file manipulation. (#35)
• Failing better now with custom error catching (#31)
• Added many internal checks for parameter inputs, warning or
  stopping as necessary - ERDDAP servers silently drop with no
  informative messages (#32)

BUG FIXES

• Using now file.info()$size instead of file.size() to be
  backwards compatible with R versions < 3.2