[pycaffe] make PyBlob a template over Dtype
[pycaffe] make PyBlob a template over Dtype

We will not actually support double nets in Python with this commit, but
this change will be necessary to create layers that embed Python.

gogartom/caffe-textmaps,gnina/gnina,gogartom/caffe-textmaps,tackgeun/caffe,CZCV/s-dilation-caffe,CZCV/s-dilation-caffe,tackgeun/caffe,gnina/gnina,longjon/caffe,wangg12/caffe,longjon/caffe,wangg12/caffe,tackgeun/caffe,gnina/gnina,gnina/gnina,gogartom/caffe-textmaps,CZCV/s-dilation-caffe,longjon/caffe,CZCV/s-dilation-caffe,gogartom/caffe-textmaps,gnina/gnina,gnina/gnina,wangg12/caffe,tackgeun/caffe,wangg12/caffe,longjon/caffe