docs(booleanAttrs): improve grammar and clarity

Closes #4392
docs(ngNonBindable): improve description

Closes #4391
docs(tutorial/step-07): fix typo

Closes #4390
docs(cookbook/deeplinking): fix typo
docs(guide/directive): improve readability and grammar.

Closes #4386
docs(ngInit): fix typo

Closes #4384
docs(guide/animations): improve wording of sentence

Closes #4405