MozStumbler v0.19.0

* Initial Greek translation (@ppapadeas, @johngian, Dimitris Papadopoulos)
* Added Lenovo P780 wifi hotspot to blocked list (@vinitraje)
* Updated Marathi & Hindi translation (@vinitraje)
* Add more on-vehicle SSIDs to the block list (@Rondom)
* Added some Norwegian transport SSIDs (@JensErat)
* Update zh-CN translation (@l-hedgehog)
* Change Intent string into more "Android" way (@tamcap)
* Update Hebrew translation (@yarons)
* Update Polish translation (@piotrdrag)