oops: Don't crash when sending fatal alert email
html: Avoid corrupting quoted style attributes

For instance, current this style we be converted as
```
<span style="font-family:'courier new';">
```
to
```
<span style="font-family:&quot;">
```

Also discard Microsoft Office specific style attributes such as `mso-list`
and friends
ui: Fixup unnecessary extra spacing in thread body
html: Trim space around `;` in @style attributes
Clear settings on department deletion

Clear ticket routing settings on topic, email or filter tables on department
deletion.
Show more dropdown for users with edit permission

Users with edit permission should be able to change ticket owner in line.
bad links fixed
Fix wrong ticket count on ticket search

Basic search is now limited to ticket number, email address and name.
faq: Don't crash when adding with validation error

On validation errors, `$faq` will be set to something non-null, like
`false`, but will not be an instance of a Faq article.