[fetch_moveit_config] fix fetch.srdf to avoid self collision and warnings

[knorth55]

This PR adds possible collision check and ignore warning.

Add possible collision check

• base_link and upperarm_roll_link can collide, but ignored in current melodic-devel.
  • check collision between base_link and upperarm_roll_link
• e-stop and r_gripper_finger_link can collide, but ignored in melodic-devel
  • check collision between E-stop and gripper

Ignore warning

• disable caster and base_link collision