Remove "experimental" notice from roswtf plugin

[130s]

Problem

roswtf/Plugins wiki page indicates Very Advanced and Experimental, which is strong phrase and I doubt that depicts the maturity well these days.

It's been 10 years since that notice was posted and in some packages the pluging has been functioning without noticeable issues reported (other than tf that added roswtf plugin in the early days, in openni2_camera a plugin was added ros-drivers/openni2_camera#80 and it had been used even in production setting (at my work).

Potential solution

• Remove notices for experimental state.
• I agree to say that roswtf plugin is advanced though. But, my guess for why the original author had to say so was:
  • It is NOT because of the technical difficulty to implement.
  • It IS because falsely configured roswtf plugin could affect the entire ROS system running on your host.

[130s]

Since it's wiki, I just added the change I suggested in the OP.

Closing but thoughts welcomed.

Forgot to mention that I'm afraid that there might have been some developers who reserved using the pluging after having seen the notice of "very advanced" "experimental".