This CL adds a remoteexec package that allows adding a configurable RBE
prefix to the template.
Change-Id: I6b4ea773f6bae5706415a1830f822db7decca92f
Test: built aosp crosshatch userdebug with and without RBE_CXX_LINKS.
Merged-In: Ica920c3d7f79f2996210b9cbd448126451c1707c
Bug: b/154820732