docs(api): example for $provide.value() uses $provide.value()

The example code for `$provide.value()` actually used `$provide.constant()`.
It now uses `$provide.value()`.

Closes #4983
Closes #4990
docs(guide/compiler): fix typo in isolate scope def

Closes #4999
docs(guide/migration): fix typo

Closes #5002
docs(guide/providers): remove extra closing parenthesis in example

Closes #5005