Complete sentence in nova cli commands section

Completed the definition for bash-completion
Added info about tab completion of commands
Fixed punctuation and ran a spellcheck of the file
Removed white spaces from patch 1

Closes-Bug: 1214505
Change-Id: I2be0c5fcf564526fa74a6f0210f174369312288d
Author: Nermina Miller
Merge "Complete sentence in nova cli commands section"