ShearerSite: Web Administration

When applying templates to a very large set of files, the output is often
not detailed enough to find the exact files on which templating failed
(because of validation errors, for example).

As an example, consider the following output:
----------
[36] => 20% done. Current file: 100043.html
[37] => The file will not be processed, because it contained 8
errors:
[38] => * Line 279. </td> tag found outside of a table. The tag was
ignored.
[39] => * Line 280. </tr> tag found outside of a table. The tag was
ignored.
[40] => * Line 281. <tr> tag found outside of a table. The tag was
ignored.
[41] => * Line 282. <td> tag found outside of a table. The tag was
ignored.
[42] => * Line 293. </td> tag found outside of a table. The tag was
ignored.
[43] => * Line 294. </tr> tag found outside of a table. The tag was
ignored.
[44] => * Line 295. Tag balance error: saw </table>, but no elements
were open
[45] => * Line 295. </table> tag found outside of table
[46] => 42% done. Current file: 100110.html
----------
I've no idea where in that range of files the error occurred, and the
template changed so little that searching for something from the old
version would be irrelevant.

It would be better if the file name was included with every error (still
keeping the line number).

Also, a detailed report at the end would be nice, such as total number of
files processed, the number that succeeded in having templates applied and
the number that failed.