Docker, installation and documentation improvements (#276)

* docker fixes

* Style fixes

* Create customize.md

* Removed docker building instructions

* Update customize.md

* Update customize.md

* Update installation.md

* Update customize.md

* Added link for customization

* Update docs/reference/installation.md

Co-authored-by: Stefania Pedrazzi <stefaniapedrazzi@users.noreply.github.com>

* Update docs/reference/installation.md

Co-authored-by: Stefania Pedrazzi <stefaniapedrazzi@users.noreply.github.com>

* Update docs/reference/installation.md

Co-authored-by: ad-daniel <44834743+ad-daniel@users.noreply.github.com>

Co-authored-by: Stefania Pedrazzi <stefaniapedrazzi@users.noreply.github.com>
Co-authored-by: ad-daniel <44834743+ad-daniel@users.noreply.github.com>