Textractor alpha release

This is the first public release of Textractor. Please keep in mind that Textractor is still in alpha state so there're probably bugs and features are limited.

Bug reports and feature requests can be submitted to the issues of this repository.

Known issues/missing features etc.:

• Only images taken with Jolla's camera are confirmed to work!
• Recognition can't be canceled due to possible memory leaks in Tesseract OCR (I have to investigate this further)
• Preprocessed image is always overwritten in new recognition event
• Image can't be cropped before recognition
• Settings are pretty complex and some parameters are missing from there (detailed explanations will be written at some point)
• Icon is the default Sailfish one, hopefully someone will make better one :)

General info:

• Language file sizes vary between 0,5 - 10 MB (they are not shipped with the application because total size would be then over 200 MB)
• results are filtered with a hardcoded confidence limit of 20 (will be added to settings)