fix for UNIQUE_TEST_TOKEN

#157 fixes the UNIQUE_TEST_TOKEN generation.
With 0.12.0, it was possible that some tokens generated in series were generated at the same ms and thus, had the same uniqid.

UNIQUE_TEST_TOKEN + BC for TEST_TOKEN

#156 restores the predictable TEST_TOKENs from 0.10.0 and earlier and adds UNIQUE_TEST_TOKEN env for the unique test tokens from 0.11.0
(for both runners)

Nested testsuites + runner support

#148 Nested testsuites support
#147 Allow custom runners

TestSuite support

#144 add support for testsuite parameter

Fixed percentage going over 100 percent

#58 Percentage going over 100.

ignore testfiles without classes

#140 :
ignore testfiles without classes

• fix for filenamed based classloading order when using namespaces

( related to #139 )

fixed selection of multilpe groups

#135 Error message when [suite is] empty + No longer runs unselected groups when multiple are selected

Optimized parser to prefer PSR0 compliant classes

#134 Prefers class names to match file names. Falls back on any class in the file
probably fixes #104

Adds error messaging to Parser when a class cannot be found.

#130 Adds error messaging to Parser when a class cannot be found.

Fix handling of special chars in JUnit XML

#127 Fix handling of '&' sympols in JUnit XML