new feature: include_glob option

Hi,

Here is a new configuration option called "include_glob" that allow you to configure a globbing pattern path to backup.

Example:

include_glob = /home/*/Documents    # Backups 'Documents' directory of all users that have their home in /home

This option only works on burp clients (it is disabled on server).
The Linux version allows the use of all globbing pattern while Windows version only support one '*' like:

include_glob = C:/Users/*/Pictures

Also note that there are still some bugs due to wrong encoding on windows when paths contains non ascii chars

Sorry in advance for the huge review you'll probably have due to the use of my own strings manipulation utilities.

As you can see, this patch is applied against burp 1.3.26, I didn't have the time to check if it would easily apply against current.

Cheers