ROS related data extraction

[KalanaRatnayake]

• Added sensitivity variation as a new Constructor

• Added get method to retrieve resolution

• Renamed dmpLinearAccelInWorld() method as dmpConvertToWorldFrame() since it needs to be used with gyro data as well

• Added example to show how to extract data required by ROS IMU message

• One doubt is whether 1G acceleration is 8192 or 16384 (At 2G resolution) because MPU datasheet says full range is 32768. For now using 8192 as it is hardcoded as gravity. Similarly using 16384 as max Gyro resolution. Please rectify this if wrong.

• Gravity value needs to be updated to use the new resolution variable to be completely compatible with resolution variation

[xpeqex]

@KalanaRatnayake

I wanted to take a moment to express my sincere gratitude on behalf of my colleagues for your recent contributions to the library.

Specifically, I'd like to highlight the following:

Corrections
User-friendliness: The modifications you've implemented made the library more intuitive and easier to use for a wider range of users.
Examples: The addition of clear and concise examples has provided invaluable guidance for others who are working with the library.

I acknowledge that there are some inconsistencies and different versions of the documentation, which can lead to confusion. I've carefully reviewed the available resources, and I'm currently unable to locate a maximum range of 32768. The most consistent information I've found points to a maximum range of 16384.

Lastly, I think this issue may help you to clarify the main doubt: jrowberg/i2cdevlib#485

Thank you again for your contributions.

[KalanaRatnayake]

@xpeqex

Thank you very much. Yeah that explanation in the jrowberg/i2cdevlib#485 seems valid.

[xpeqex]

I will do some test with the changes to then merge this PR :)

[xpeqex]

LGTM, nice improvements.