Explicitly compile with -fPIC and link with -pie: work-around for 32-bit builds with NDK r17c.

remove string resources used by removed in 3.1.0 preference "Allow PATH prepend(allow_prepend_path)"

remove string resources used by removed in 3.1.0 preference "Allow PATH extensions(do_path_extensions)"

Based on "SecureBox Pro" functionality: command aliases and shell startup script.

Allos paths to be used outside activities.

Imported from "SecureBox Pro".

Imported from "SecureBox Pro".

Used for first time in Android Studio 3.5.

Restore previous code but now in synchronized statement.
Also let restore set of "is running" flag before to start threads.

Properly restrict index as palette has pre-defined set of 256 colors only.
Also simplify color palette creation.

Fixes issue #19 - avoids crash on invalid color index (outside palette size).

(changed background color of rounded version to match base)

update "Google Play" description with warning related to use of "shared user id" and upgrade failure