rename meter table to sample

as we branch common meter definition data to it's own table,
we rename table containing raw data to more appropriate name:
sample

blueprint: meter-table-sql
Change-Id: I55c86540098225a3d52116df8b27854483921ee9
sample table contains redundant/duplicate data

create a meter table to store meter definition attributes:
- name
- type
- unit

blueprint: meter-table-sql
Closes-Bug: #1211985
Change-Id: I4dd510e66d64226b03cfce8d7dd5e77937793ba3
Merge "rename meter table to sample"
Merge "sample table contains redundant/duplicate data"