Clang tidy: include check `google-readability-braces-around-statements`

[exclowd]

As mentioned in issue #112. This PR adds two earlier excluded clang-tidy checks:

• google-readability-braces-around-statements
• readability-braces-around-statements The tests were not refactored because of incoming major changes proposed in #122. Both the tensor implementation and the examples were refactored. Moreover, since there is no definite style guide, I did not refractor too aggressively and tried to match the general style of each file to the most part so as to not make some lines stand out.