Initial add networking doc
Count the NULL objectid as already transferred for the purposes of
fetching
Merge remote-tracking branch 'origin/pr/311'
Merge pull request #420 from dwins/http-clone-empty-repo

Count the NULL objectid as already transferred for the purposes of fetching
Minor fixes and changes to cli plumbing commands (blame and diff-tree)

Minor edit to documentation
added raw version to show command
Made diff-tree use plumbing DiffTree operation instead of DiffOp

Adapted functional tests for diff-tree
Fixed issues in show command