Deprecate Ice 3.3 and note its removal for 5.1

[ghost]

• Backport documentation fixes from 5.1 (use current doc links)
• Examples are based on Ice 3.5
• Ice 3.5 will work on Windows from 5.0.2 onward, so remove comments saying otherwise
• Ice 3.3 support is deprecated in 5.0 and will be removed in 5.1

--rebased-from #760

[hflynn]

We need to clarify if we are claiming Ice 3.5 is supported for Windows for 5.0.2, sounds like @sbesson and @joshmoore might prefer to target 5.0.3, so this PR may need to be left on hold until after the 5.0.2 release. We can discuss the other work that is required when Seb is back.

[ghost]

@hflynn Please note that's only a tiny part of this whole PR--like a sentence--and can be reverted if needed. No need to put the whole thing on hold, there's a number of improvements in addition to that.

[hflynn]

Ok, this can be reviewed tomorrow and I'll just make a note that the Windows installation doc may need to be reverted for 5.0.2 if merged.

[ghost]

I've removed Ice 3.5 as being supported for Windows in 5.0. This can be addressed separately from the deprecation of Ice 3.3, so this PR is now solely focussed on updating the Ice links and noting Ice 3.3 as being deprecated.

[hflynn]

Thanks @rleigh-dundee, that does make it easier to keep track of things for the release.

[joshmoore]

Other than possible link check issues that are ongoing, 👍

[hflynn]

Link is fixed, Jenkins is green again so merging.

[hflynn]

N.B. When we confirm Ice 3.5 support for Windows, as well as the commit above being reverted, https://www.openmicroscopy.org/site/support/omero5/sysadmins/limitations.html#ice-3-5 will need deleting too.