Fix bug with progress bar when sweep is delayed

When a delayed sweep started, the progress bar showed a broken HTML
string 'unknown">' due to a lack of translation string for the title of
a sweep with this status.  The class names for the progress bar layers
were also coming in with 'NaN', due to a divide-by-0 error.

This commit fixes both of those issues by adding a translation string
for the status of a delayed sweep ('Delayed') and checking that the
total number of sweeps is greater than 0 before dividing the
sub-totals.
Fix typo in ProjectsController#create that showed 'destroyed' text

There was a bug that meant that when a user created a new project, the
text that actually appeared in the system message was
"Project was successfully destroyed."

I'm sure it was meant to say "Project was successfully created."
Now it will.
Merge pull request #121 from flarnie/minor_bug_fixes

Minor bug fixes