improve readme as suggested by Mike
update readme.pdf as suggested by Mike
updated Tabs.strings
Merge pull request #265 from rantom/master

Translated "Tabs.strings" to Finnish
update Czech translation
remove duplicite keys in English translation files
make translation propagation sticky when moving keys between files
propagate duplicit keys cleanup
improve validate task to report duplicate keys
remove duplicit keys from English.lproj
propagate removal of duplicit translation keys
propagate SYSTEM key