The Colour Grading Tool allows you to make synchronised colour adjustments. These adjustments changes are applied to the whole movie nondestructively, on a clip-by-clip basis (so changing the colour of one movie doesn't affect any other movies in the Playlist unless the Apply to All media is specifically ticked).

You can load the Colour Grading Tool by selecting it from the Tools menu or by pressing the Pro button on the Minimal View Transport Controls. The Colour Grading Tool button is represented with the letters RGB.

 
There are controls available to adjust Brightness, Gamma, Contrast and Saturation.
These controls are synchronized, meaning that any changes made will be shown across all the users in the session. The Gamma can be changed so that only your gamma is changed - this is located in Drawings/Colour tab in the Preferences. 

 
Any colour adjustments you make will be seen by everyone else in the the review.

You can isolate and render individual colour channels via the Output selection.

The range can be selected from the file, video or the full range.

Colour grading settings can applied across all files in the playlist by selecting the 'Apply changes to all movies' or it can copied and pasted across separate files using the menu option under 'Tools' or ALT-J for copy / ALT-H for paste. To use, change the colour settings as required on a media file then select copy, change to the next media file and paste the colour settings. 

The OCIO settings are explained here.