Add ability to specify a condition which will skip lines.

[cpmcgrath]

The purpose of this is to allow code alignment to skip lines. If you have

int value1;
//Something about value2
string value2;

and you want to use align by space to align the variable names you end up with

int         value1;
//Something about value2
string      value2;

This option would let the center line be ignored.

We may also proved an option on the Align by screen to ignore this or not.

Finally, this will only skip whole lines, not part of lines after the specified condition. So it would not stop

 int foo; //comment after code
 var valueone = 64;
 var valuetwo = 64;

becoming

 int foo; //comment after code
 var valueone       = 64;
 var valuetwo       = 64;