Returns a formated String of a given linevector.
retstr = format_linevec(lvec [,style])
Linevector or matrix.
seperator, default ', '.
Returnstring.
Formats one or more Linevectors (matrix) with seperators and returns a string for each line.
The styleparameter describes the used seperators, it can containe aditional characters.
(matrix aware)
No warranty, there are no inputchecks.