change some repo to our github site

Change-Id: I58a9c4ad6acd68ecb4383d896fd4cad99d19cadc
Merge "change some repo to our github site" into kitkat
Merge "Add some git/gerrit related code to  README" into kitkat
update to android-4.4.2_r1

Change-Id: I68fbb9ae60688fafb1bb7f3c2f43ffa5a1c8e1e4
Merge branch 'kitkat' into kk-ssh