Typo fixed

Update mismatched end tag for code example in section 'Loops'

gh-pages-golang-flowControl-forLoops

Add the description for the For Loops and For-Range loops.

Update composer.md

`update --lock` is useful e.g. after resolving merge conflicts when the packages should stay at their current versions but the lock file hash is invalid and must be updated.

Minor improvements

Fix typos

Just made some things clearer by comments.

s/keywodrs/keywords/

Update the "every Sunday midnight" example

Added `f` character jumps

Update elixir.md

Correct spelling mistakes.

Chai: Add lengthOf for BDD section

Update elixir.md

Add Docker support for development

Unhide Knex

I believe this was the intention, ~s[ ] seems to not do anything, but ~s| | seems to have the effect described.

small typo

ecrt -> cert

Added the `f` and `F` character jump to Navigation.