lineedit: use read_key to recognize ESC sequence.

This fixes several vi mode bugs and prepares for further fixes.

function                                             old     new   delta
read_line_input                                     3287    5511   +2224
remember_in_history                                    -     499    +499
lineedit_read_key                                      -      70     +70
read_key                                             321     332     +11
input_tab                                           2823       -   -2823
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(add/remove: 2/1 grow/shrink: 2/0 up/down: 2804/-2823)        Total: -19 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
3 files changed