Reorganized the icons code a bit.

Return 404 instead of 400 when no accounts breached.

Trim spaces from admin token during authentication and validate that the admin panel token is not empty

Added newlines to config options to keep them a reasonable length.

When the iconlist was smaller then 5 items, it would cause a panic.
Solved by using .truncate() on the iconlist.

Loop for a maximum of 5 times through the iconlist or until a
successful download of an icon.

 - Created a separate function for parsing the sizes attribute
 - Parsing sizes now with regex
 - Should work with any non-digit separator

Some sites use XSRF Tokens, or other Tokens to verify a subseqense
response. The cookies which are sent during the page request are now
used when downloading the favicon.

A site which uses this is mijn.ing.nl.

 - Using url from reqwest to fix href, this fixes:
   + "//domain.com/icon.png"
   + "relative/path/to/icon.png"
   + "/absolute/path/to/icon.png"
 - Removed fix_href function
 - Some variable changes