perf-studio-ctrl: handle non perf cache directory

Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>
perf-studio-ctrl: add edit command to spawn editor

Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>
readme: clean documentation

Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>
add install tips file

Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>