Strip rear lines from text
# Arguments
- a_count : Count of lines to strip ( trimmed )
- a_content : Content to strip
# Demo
```
% Strip examples from manual
% Although not all example is a single line
$striprl|(4,$syscmd(rad -M strip))
$countl-()
===
22
```
# Example
$assert(a$nl()b,$stripfl(1,c$nl()a$nl()b))