Version 1.0 with Windows and Android support

This is an initial release.

Windows:

• Open plain text
• Open SFV-encrypted files. Supports all formats used during the developement until this moment (legacy, SFV1, SFV2).
• Save SFV-encrypted files. Save format: SFV2.
• Built-in brute-force cracker to estimate the strength of encryption.
• Command-line /decrypt {file-location.txt}

Android:

• Supports Open and Share commands (tested: file managers on Android 5, 8 and 9; Total Commander; OneDrive).
• Shows error message when something is wrong.
• When open without the command (clicking the icon) - shows text description (I haven't learned yet how to get rid of the desktop icon and default activity).
• Android package is so big because it includes entire Mono runtime :( I will try to exclude unnecessary stuff in the future.