* add trace op

* bug fix

* bug fix; test=develop

* thrust bug fix; test=develop

* remove useless register; test=develop

* fix bug; test=develop

* update trace kernel; test=develop

* move kernel args to trace_sig; test=develop

* modify kron OP to complex template types

* modify reshape, slice, trace, transpose OPs to complex template types

* modify to complex template types in eigen slice files

* change to complex template types for pad.cc and pac.cu

* format code style

* add trace op_register_version and fix defaulf bug; test=op_version

* add trace op_register_version; test=op_version

* add trace op_register_version; test=op_version

* add trace op_register_version; test=op_version

* fix missing the template bug of vector; test=op_version

* add complex64 and complex128 type; add +-*/@ and slice opreator for complex types

* add test cases for complex elementwise, matmul and getitem unittest

* add test cases for complex types

* add test cases for complex matmul unittest

* kron, reshape, transpose support complex types

* sum and trace op support complex types

* add test case of sum and trace op

* fix the bug of imag part of complex not initialized

* format file

* format code style

* kron support type promotion; modify test cases

* add trace op, test=develop

* Optimized the implementation of trace op, test=develop

* fix a bug of include in trace_op.h, test=develop

* move trace API from creation to math, test=develop

* modified en doc. test=develop

* add complex trace api

* add complex sum api, test=develop

* modified en doc of complex sum and trace, test=develop

* modified doc and trace API, test=develop

* modified en doc of trace and sum, test=develop

* modified comment in complex kron API, test=develop

* OP Should Not Have Unused Input, test=develop

* add GetExpectedKernelType, test=develop