Use more clear status marks

[stokito]

Instead of bullet for status and plus for health we can use more known symbols:

I chose this symbols because they are part of Unicode 1993 and should be supported by all fonts.

• ☼ sun for healthy
• ⚠ warning for unhealthy
• ◌ dotet circle for starting

Please check how they looks in iTerm on OSX. Unfortunately they wont be shown correctly on Putty from windows because it uses Currier New font but previous statuses wasn't shown ether.

[mtklr]

Thanks, I really like this change and hope it gets merged eventually - red-green color blindness makes it really difficult to differentiate the default symbols. (It would also be nice if the symbols were user-configurable.:)

[stokito]

I don’t think it worth to make configurable but agree that green/red colors doesn’t work for color blind peoples. But this may be changed by theme. Maybe even current reversed theme will be better for color blind peoples.
The most I concerned is about symbols to be clear and how they look in terminal fonts.
Personally now I don’t feel right about using the dotted circle but as far I remember all other symbols looked much worse. I hope that containers will start so fast so users not even notice the circle.