Enhanced coloring of differences

[Removed by request]

I'm using Ubuntu 15.10 dev with git-gui 1:2.5.0-1 and currently only the lines are colored for added/removed ones. Maybe the differences in the lines which characters are added/removed can be colored too (for example with a higher opacity) to make them easier to see.

[Removed by request (removed3425744)]

I have noticed that there is the --word-diff option that does this. But all modes do have also some disadvantages:

color, plain: They show the added and removed words on the same line without coloring the line itself which makes the changes hard to check for long lines.
porcelain: It shows the added and removed words on new lines which makes them easier to read but the tilde makes the changeset quite big.

Also all these variants break the usual diff format and maybe this is the reason why none of them is enabled at default.

The in my opinion most effective variant so far that I have seen was either on SourceForge or GitHub. If I remember correctly the background of the characters from the word differences were just colored with a higher opacity to make them easy to see. I think it would be useful to add another variant to --word-diff to add this or a similar behavior. Also since it would not break the usual diff format this could then maybe made the default.

[Removed by request (removed3425744)]

Also I'm noticing that currently at default word differences for whitespaces are colored if they change. Eventually this behavior should then be bound/enabled to --word-diff and/or to the suggested mode.