Mark "ago" travel-times better to avoid confusions

[Porrumentzio]

Acknowledgments
Please check the following boxes with an x if they apply:

• The feature I want to propose would be useful for the majority of users, not only for me personally.
• I am aware that Transportr is mostly developed by one person in their unpaid spare time.
• I can help myself to get this feature implemented or know someone who wants to do it.
• If I want to add support for a new region or country, I checked that this is already available in public-transport-enabler and know the process described on the Transportr homepage.

Is your feature request related to a problem? Please describe.
When searching a travel and selecting a way/line, if pulled down there appears previous ways/lines, which are already in the past.
This past ways/lines are not distinguished in any way from the future ones, getting the user into confusion.

Describe the solution you'd like
The past ways/lines could be distinguished using another color, clearly, and also marking with a thick line the limit between past and future ways/lines.

Describe alternatives you've considered
Past ways/lines could be not displayed.

Additional context
Actual state with light theme:

My proposal:

[ialokim]

Thanks a lot for your suggestions! This specific issue is a duplicate of #593. You might post your mockups again over there.