Orthanc config instructions do not cover some of the options

[Ed McDonagh]

mkdir_cmd and dir_sep are explained in the file, physics_to_keep_folder is self-explanatory, but the following two could do with appearing, along with linux alternatives:

• zip_executable
• rmdir_cmd

[David Platten]

Updated example Orthanc configuration file and associated document to include a little more information on Linux commands. Doc update only [skip ci]. References issue #654

→ <<cset 9b74097074f4>>

[Ed McDonagh]

Added ref #654 to changes. [skip ci] docs only

→ <<cset 51a96f9e3f0b>>

[Ed McDonagh]

Merged in issue648etcDocsFor081 (pull request #214)

Fixes #647, #648, #649, #650, #654

→ <<cset d1b822782c6c>>

[Ed McDonagh]

Merged in release-0.8.1b2 (pull request #216)

Release 0.8.1b2

Some fixes, lots of docs. Refs #647, #646, #647, #648, #649, #650, #651, #652, #653, #654, #656

→ <<cset d5db3ea11366>>