From these errors it looks like the paths are pointing to folders that don't exist (because you're moving from a local setup to live). Have you ever used a multi-environment config like Focus Lab's Master Config?
Since you can't log into the control panel and it looks like the issue has to do with paths, you could get the paths reconfigured using a multi-...
You probably have to trigger Matrix's update script. Go to Add-Ons → Fieldtypes → Matrix and it'll run automatically.
If that doesn't work, try turning on error messages for admins and see if that gives you some hints. In system/expressionengine/config/config.php, put $config['debug'] = "1";
First, disable gzip compression in the config (gzip_output = 'n'): https://ellislab.com/expressionengine/user-guide/general/system_configuration_overrides.html#gzip-output
Then, look at the error that appears when refreshing the page :-)
(of course, $debug must be 1 for the error to show)
Also P&T add-ons seem to have been particularly affected, users reporting issues with Playa, Matrix etc.
There's no ETA on a fix right now just that one is coming with the 2.8.1 release. So I'm playing safe and sticking with 2.7.3
It looks like you still have references to your local filesystem for both your themes folder and your templates folder.
These values might be set in your config.php file, or directly in the database. (If you set them via config, you can override any bad values in the database.)
Pop these in your config.php file to fix this up:
In my experience a white screen is always a suppressed PHP error. If you can't get the error to show, something is still suppressing it.
Instead of going back and forth with comments, we jumped on Skype. In this case, disabling extensions in the config.php file got the PHP error to show up on the screen. This is an EE1 site so we used: