add GetExternalLinkUsage; different fixes

new function GetExternalLinkUsage for receiving information about
external links on a MediaWiki project; fixing some counting bugs in
GetTransclusions and GetCategoryMembers; add "About" button to log
window; fixing bug in log window.
oops

oops... this testing stuff shouldn't be here.
Quantity datatype for Wikidata, Emailuser

add support for quantity datatype to WikibaseEditEntity and
WikibaseGetEntity
add possibility to send mails using PBWB
add new commands

add PBWB::ProtectPage, PBWB::BlockUser, PBWB::UnblockUser,
PBWB::MassMessage; fixes to PBWB::EmailUser
cosmetic changes; bug fix

- autoresize list columns in log window
- show version in title bar
- end program after FreeFramework() completely.
Merge pull request #2 from inkowik/pbwb-1.60

pbwb 1.60 release