Don't exit for some missing capabilities
Don't exit for some missing capabilities

All terminal capabilities used are not critical for pick to behave
correctly, such as {enter,exit}_ca_mode and cursor_{invisible,normal}.
This change makes pick work in OpenBSD console where TERM=v100.

DBOTW/pick,prahlad37/pick,calleerlandsson/pick,DBOTW/pick,thoughtbot/pick,thoughtbot/pick,thoughtbot/pick,DBOTW/pick,calleerlandsson/pick,calleerlandsson/pick,prahlad37/pick,thoughtbot/pick,prahlad37/pick,prahlad37/pick