Name Changes for sample and dynamic_vino_lib packages.

[sradmard]

As discussed in #63 the names are changed as follows:

• dynamic_vino_lib -->vino_core_lib
• sample --> vino_sample
• people_msgs --> vino_people_msgs

[LewisLiuPub]

@sradmard thank you very much for your contribution, appreciate it!
In order to reduce the potential impact to the previous version, I am creating a new "stable" branch to archive the current code.
I suppose you have already tested this PR before you committed it, I may merge it to branch master once new branch created. Meanwhile, I am finding some resource to do more regression tests.

Thanks again.