Handle negative numbers in UIUtilities.findDecimal() (Fixes #11484) (rebased onto develop)

[jburel]

This is the same as gh-1571 but rebased onto develop.

---

Ticket for reference with more overarching explanation:

• https://trac.openmicroscopy.org.uk/ome/ticket/11484

Test case to be run as follows:

./build.py clean build
...
cd components/insight/build/
ant -Dtest.suite.include=**/shoola/util/ui/TestUIUtilities.java test
...

Both unit tests should pass.

[jburel]

--rebased-from #1571

[mtbc]

    [junit] Testsuite: org.openmicroscopy.shoola.util.ui.TestUIUtilities
    [junit] Tests run: 2, Failures: 0, Errors: 0, Time elapsed: 0.254 sec

Good to merge.

By the way, that's an interesting way to run a test. I wonder if it deserves a mention in the documentation on developers/testing.txt or developers/Insight/Contributing.txt.

[joshmoore]

@mtbc: agreed. This is a glimpse into how the insight build itself works. Time to enable a few tests by default from insight/build.xml? /cc @bpindelski.