Merge branch 'feature-string-creater' into develop

.../base/utils/boundary/bicreater/BiCreaterStringAppend.java

...base/utils/boundary/bicreater/BiCreaterStringBetween.java

...base/utils/boundary/bicreater/BiCreaterStringCombine.java

...utils/boundary/bicreater/BiCreaterStringIntersection.java

.../utils/boundary/bicreater/BiCreaterStringLowerBounds.java

.../utils/boundary/bicreater/BiCreaterStringUpperBounds.java

...z/fgbks/base/utils/boundary/checker/CheckStringEqual.java

...bks/base/utils/boundary/checker/CheckStringInContact.java

...gbks/base/utils/boundary/checker/CheckStringSubsumes.java

...fgbks/base/utils/boundary/creater/CreaterStringLower.java

...oblenz/fgbks/base/utils/boundary/impl/StringBoundary.java

.../utils/boundary/bicreater/BiCreaterStringBetweenTest.java

.../utils/boundary/bicreater/BiCreaterStringCombineTest.java

...s/boundary/bicreater/BiCreaterStringIntersectionTest.java

...s/base/utils/boundary/creater/CreaterStringLowerTest.java

...nz/fgbks/base/utils/boundary/impl/StringBoundaryTest.java