Move gits from people to more appropriate places

Headline:
Linaro Android builds are now referencing gits at more permanent locations

Acceptance:
All supported manifests in a release are free from people/ gits

Notes:
This will be a multi-cycle effort due to each git being in flux.
Gits with strong ownership in Linaro outside of Android will not be moved.

Example: For 11.09 these will be the only remaining in default.xml:

people/tomgall/libjpeg-turbo
people/afrantzis/glmark2

Work items:
Find each people/ reference: DONE
[pfalcon] Migrate people/bernhardrosenkranzer/android-kernel-iMX53 => gerrit:kernel/imx53.git: DONE
Migrate kernel/origen.git to http://android.git.linaro.org/: DONE
Migrate kernel/snowball.git to http://android.git.linaro.org/: DONE
[pfalcon] Migrate people/bernhardrosenkranzer/iMX53 => device/linaro/imx53: DONE
[pfalcon] Migrate people/bernhardrosenkranzer/x264 => platform/external/x264: DONE
[pfalcon] Migrate people/bernhardrosenkranzer/ffmpeg => platform/external/ffmpeg: DONE
[berolinux] Migrate people/bernhardrosenkranzer/mmtest => platform/packages/apps/mmtest: DONE
[berolinux] Migrate people/botaosun/busybox => platform/external/busybox: DONE
[berolinux] Migrate people/bernhardrosenkranzer/libvpx => platform/external/libvpx (new branch): DONE
[amitdanielk] Migrate people/amitdanielk/library/libnl => platform/external/libnl: DONE
[amitdanielk] Migrate people/amitdanielk/library/ncurses => platform/external/ncurses: DONE
[amitdanielk] Migrate tools/powertop => platform/external/powertop: DONE
Host the clone of https://gitorious.org/uim/ at device/ti/uim : DONE
Determine which are Android-specific: DONE
Move each Android-specific git to android.git.linaro.org: DONE
Change all manifests that reference these gits: DONE
Test builds for all changed manifests: DONE