Add unit tests for Parser File class
Add test for Parser and refactor parse method
Add phpunit.xml to ignore file
Worked on documentation for creating custom templates
#1131: ConstantConverter errored when Namespace was a string

In some circumstances the namespace may be a string; in these cases
the code threw a fatal error because it could not resolve the FQSEN
of that Namespace. This commit resolves the issue by tightening the
checks.