Support multi-label merge into one node label

Support multi-label merge into one node label
1. we want to support multo-label like SSD,GPU,FPGA label merged into single machine, joined by &. like SSD,GPU,FPGA-> SSD&GPU&FPGA
2. we add wildcard match to extend the job request. we define the wildcard like GPU, it will math all the node labels with GPU as part of multi-label merged label. For example, GPU will match SSD&GPU&FPGA, GPU&FPGA. We define SSD&GPU&FPGA=

, so the job can run on SSD&GPU&FPGA node.