utilize tokenizer for use indexing

[goatherd]

Supplied a test case for Analyzer::useIndexing() and re-implemented the method using the tokenized source.

Performance impact is roughly halved for both memory and execution time of this step.

[mauris]

Hi @goatherd :D Thanks for the awesome move to use tokenizer. I've briefly gone through the patch and saw that a case has been left out. use can also be used within class{} to denote usage of traits by the class.

[goatherd]

Hi @thephpdeveloper,

the method is described as get all use declarations by alias. Use statements in class context do rather consume than declare a namespace. Therefore the parser will stop on the first occurrence of a class/interface/trait keyword.