Fix Downloadable contract
Handle bad download_path
Update outdated description for download command

Update the description of the configure command to display the correct alias -d for the --download-path option. This was forgotten when the alias changed from -l to -d in commit 15016c79ad017a92a5c08fededa5854471026ded.

(I would also vote for using the more explicit --email --password and --download-path options in the description but did not include them in the PR.)
Merge pull request #27 from sebroeder/patch-2

Update outdated description for download command
Merge pull request #18 from leafac/fix-download-path-invalid

Fail gracefully when `download_path` isn't valid
Fix possible typos
Merge pull request #32 from paulog/possible-typos

Fix possible typos
Merge branch 'master' into fix-issue-28