"Fretch From Upstream" and "Push To Upstream" is alway grayed out
1. Right click your project, choose Team→Show in Repositories View. You will switch perspectives and be in the Git Repositories tab.
2. Right-click "Remotes" and choose "Create Remote". For "Remote name", enter "origin". Click OK.
3. Click Change. Enter your information as you did during your initial push. Click Save.
You should now be able to push by merely right-clicking on your project, then Team→Push to Upstream.
Because the remote was added under the project in question, each project can have its own upstream origin and they will not interfere (whereas the Window > Preferences solution is a global setting).
... Use the name "origin" for the remote, which is absolutely necessary."