More subtle default color scheme

While the bright yellow marker, green paths and yellow line number are well intentioned and work well when there is one or two matches, a screenfull of those makes it harder to read the text and spot what one was looking for, at least for me. Also, to me, the bright yellow feels abrasive.

The proposed changes are for making the color scheme more subtle and making the overall text easier to read.

People can still "--color-match '30;43'" if they like to be punched in the eye, colorwise.