Docs: Build instruction to checkout release version.

Signed-off-by: matematik7 <domen.ipavec@z-v.si>
Docs: Manual start/stop of service instructions.

Signed-off-by: matematik7 <domen.ipavec@z-v.si>
Docs: Added info for build with HTTPS.

Signed-off-by: matematik7 <domen.ipavec@z-v.si>