Sachesi v1.9.0

Changelog:
Introduce a download manager for 'Download All'. Saves to temporary files which support resuming.
Rewritten extractor code. Generate extracted names by inspecting file. Detect file type by looking at header.
In Search results, uncheck already downloaded results by default and show these to the user as "(downloaded)". Also improve the sort to have OS and Radio on top and downloaded at the bottom.
Improve installer and search progress. Show position in installation.
Change the advanced toggle button to a native button (in center).
Change reported OS/Radio in status bar to the versions reported by installed apps, which appears more accurate.
Add alpha/alpha2/beta2 servers.
Update the device variants.