Fix args in wprofile, add -e option.

Remove getopt to allow arbitrary ordering in arguments (mixed with positional
arguments). Add -e option to open profile in default editor ($EDITOR variable).
Update documentation.

Add wprofile -e documentation to the README.
Catch error if not able to connect to internet.

Print error message and exit if connection to wunderground cannot be
established.
Allow array indexing in format string.

If the key is a numerical value, it will be parsed as an integer and used to
index into a JSON array rather than as a string key.