Rewrite paragraph on installer managed files

[ekohl]

This makes it clear why the installer manages the files. Rather than presenting it as a downside, it explains why it's a feature.

The part about DHCP and DNS is dropped since there are no instructions to set up DHCP and DNS here. If anything, they should be presented in the correct chapters.

Builds on #2690 and currently a draft because of that.

• I am familiar with the contributing guidelines.

Please cherry-pick my commits into:

• Foreman 3.9/Katello 4.11 (planned Satellite 6.15)
• Foreman 3.8/Katello 4.10
• Foreman 3.7/Katello 4.9 (Satellite 6.14)
• Foreman 3.6/Katello 4.8
• Foreman 3.5/Katello 4.7 (Satellite 6.13; orcharhino 6.6)
• Foreman 3.4/Katello 4.6 (EL8 only)
• Foreman 3.3/Katello 4.5 on EL7 & EL8 (Satellite 6.12 on EL8 only; orcharhino 6.4/6.5 on EL8 only)
• Foreman 3.2/Katello 4.4 on EL7 & EL8
• Foreman 3.1/Katello 4.3 on EL7 & EL8 (Satellite 6.11 EL7/8; orcharhino 6.3 on EL7/8)
• We do not accept PRs for Foreman older than 3.1.

[github-actions]

The PR preview for 50f2099 is available at theforeman-foreman-documentation-preview-pr-2694.surge.sh

The following output files are affected by this PR:

• Installing_Server/index-foreman-deb.html
• Installing_Server/index-foreman-el.html
• Installing_Server/index-katello.html
• Installing_Server/index-orcharhino.html
• Installing_Server/index-satellite.html
• Installing_Server_Disconnected/index-satellite.html

show diff

show diff as HTML

[ekohl]

Rebased now that #2690 is merged.

[adamlazik1]

LGTM

[Lennonka]

@ekohl Can this be cherry-picked all the way back?

[ekohl]

@ekohl Can this be cherry-picked all the way back?

Yes, since Foreman 3.1 I'd say this is correct.

[Lennonka]

Cherry-picked:

• e1a397b..18d8183 3.9 -> 3.9
• fea3861..bd37c6a 3.8 -> 3.8
• c6ef160..75a45b6 3.7 -> 3.7
• 513ad6b..fb32505 3.6 -> 3.6
• c3181f3..08759f1 3.5 -> 3.5
• 5f7b7f5..835ea16 3.4 -> 3.4
• 933ab3a..8e44513 3.3 -> 3.3