if flash gecko, then un-install com-ril. set KEEP_COMRIL=1 will skip this step.
[auto_flash_from_PVT.sh]
[auto_flash_from_TWCI.sh]
[uninstall_comril.sh]
Modified the tab/space
Set keeping com-ril by default, removed KEEP_COMRIL.
Set UNINSTALL_COMRIL=true to un-install com-ril.
Merge pull request #68 from askeing/uninstall-comril-when-flash-gecko

If shallow flash the gecko, user can set `UNINSTALL_COMRIL=true` to un-install com-ril from device.