* Remove hard coded dialog size and let the sizers do their job.
* Minor UI policy text fixes.
* Minor text changes to improve readability.
* Minor tool tip changes to improve readability.
File "rules" has instructional text as comments near top.
2) Convert all text files in repo to LF line ending form.
Any checkout done with "rules" in play will convert the working
tree to native line ending, while keeping repo as LF line ending.
* Add visible clearance when edit node or track segment,
add parameter "show clearance for new or edited track with via area"
in "Display options" menu.