Release v2.2.3

A new source code file was added for TIntegerRange.

Meta data for TIntegerRange was added to structs.ini.

Created a new DUnit test project for the Structures category, for
compilation with Delphi XE only. This is TestCatStructsXE.dpr/.dproj

Added unit tests for TIntegerRange to the a new TestUStructCatSnippets
unit.

Generated a new UStructCatSnippets unit from CodeSnip that includes
TIntegerRange.

The TestCatStructsXE DUnit test project was added to
CodeSnippetsTestsXE.groupproj.

Fixes #56

Added tests to TestUStructCatSnippets unit for all snippets in the
Structures category except for TIntegerRange, which was the only snippet
in the category to have tests.

Advanced records had dedicated unit test classes. The remaining simple
record types and functions had tests grouped together in a single new
unit test class.

All but one snippets in structs.ini had the same advanced testing
information added to it that sets TestInfo=advanced,
AdvancedTest.Level=unit-tests and AdvancedTest.URL to the Cat-Structs
unit tests on Github.

The only snippet not so updated was TIntegerRange, which already has the
same test info.

The snippet description for the `Range` snippet had its description
fixed not to claim that a range of length 1 was empty.

The `TRangeEx` advanced record had a warning added to its extra
information re buggy behaviour if the range's lower bound was set
greater than the upper bound.

Removed the unused Setup and TearDown methods from the test class.

Removed commented out test code from the class implementation.

Fixes #58

Added tests to TestUArraysCatSnippets unit for all snippets in the
Arrays category that didn't already have them.

Added advanced testing information for all snippets in arrays.ini that
didn't already have it: all snippets in this category now have unit
tests in the same DUnit tests project.

Set TestInfo=advanced, AdvancedTest.Level=unit-tests and
AdvancedTest.URL to the Cat-Arrays unit test project on Github.

Noted that all snippets in Arrays category now have unit tests.

Added warning that newer tests are only checked for compiling with
Delphi XE and later.

Corrected some errors and inconsistencies.

Fixes #38

A new source code file was added for RandomString

Meta data for RandomString was added to string.ini.

Added unit test for the RandomString to TestUStringCatSnippets unit.

Regenerated UStringCatSnippets using CodeSnip to contain the
RandomString function.

Fixes #28