Streamlined data import and export by making assumptions that the user
is probably willing to make: 'import()' and 'export()' determine the
data structure from the file extension, reasonable defaults are used
for data import and export (e.g., 'stringsAsFactors=FALSE'), web-based
import is natively supported (including from SSL/HTTPS), compressed
files can be read directly without explicit decompression, and fast
import packages are used where appropriate. An additional convenience
function, 'convert()', provides a simple method for converting between
file types.