[wait for upstream] Add nodes to adjust the volume of the auto speaking

[Kanazawanaoaki]

I wrote a node to change the volume of audible_warning and tweet in order to adjust the volume of warnings etc. that pr2 automatically speaks during lab meeting.

this PR needs jsk-ros-pkg/jsk_roseus#729 and #1725 .

related to #1724

cc. @knorth55 @iory

[Kanazawanaoaki]

Added volume controls for /tweet_client_tablet, /tweet_client_uptime, /tweet_client_warning and /tweet_client_worktime.

[Kanazawanaoaki]

I added apps with temporary image.

[knorth55]

can you move these apps in jsk_robot_startup and use the same apps for fetch?

[knorth55]

@Kanazawanaoaki can you open the similar PR whose target branch is develop/pr2?

[Kanazawanaoaki]

Sorry for the delay. I open #1744.

[Kanazawanaoaki]

Currently, develop/pr2 and develop/fetch only include changes related to the each robot, but I think the following changes and discussions are ideally needed for this functionality.

• Create and change icons.
• Determine the location of the App. I have now added Apps to jsk_pr2_startup and jsk_fetch_startup, but since fetch and pr2 are common as programs to be executed, I thought it would be OK to add them to jsk_robot_startup's App if there are no problems.
• Come up with a name for your App or program

[Kanazawanaoaki]

I changed the location of the apps and the icon images, and tested the contents of this PR in robot body with #1746 and #1745.