* Shim fixes (in component tests) in light of changes to xTests (#84)
* `stlsoft::basic_static_string<>` : MinGW compatibility (#86)
* ~ shim fixes (in component tests) in light of changes to xTests
* + added optional dependency to **shwild**, so as to allow **xTests**' pattern matching constructs to be used
* `stlsoft::basic_static_string<>` : ~ preparatory tidying
* **test.unit.stlsoft.string.static_string** : + tests for `length_error`
* Added `platformstl::environment_variable_scope` (#85)
* ~ shim fixes (in component tests) in light of changes to xTests
* + added `platformstl::environment_variable_scope` ; + added **test.component.platformstl.system.environment_variable_scope** ;
* Miscellaneous fixes (#87)
* ~ shim fixes (in component tests) in light of changes to xTests
* ~ preparatory tidying
* **include/unixstl/system/directory_functions.h** : ~ minor improvements to API signatures
* + brought over **test.unit.stlsoft.string.copy_functions**
* + brought over **test.component.platformstl.system.system_traits**
* ~ post-merge improvements
* **test.unit.stlsoft.util.string.snprintf** : ~ warning suppression
* **test.unit.stlsoft.string.copy_functions** : ~ warning suppression
* release
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Co-authored-by: Matt Wilson <matthew@synesis.com.au>