doc: minor fixes event-loop-timers-and-nexttick.md
Checklist
-
documentation is changed or added -
commit message follows commit guidelines
Affected core subsystem(s)
NONE
Description of change
Minor fixes and enhancements to event-loop-timers-and-nexttick.md
- Added missing "be"
- Added a link to REPL docs
- Added definition of libuv and a link