Add tests for command splitting and fix root tests on Windows

Fix test failures on Windows.

websocket: Refactored to use gorilla instead of golang/x

I had commented out this check just to make sure the rest of the test cases were succeeding and forgot to add it back in.

NewTestController now sets the site root to '.' to accomodate Windows.  This introduced a failure on Linux because we join "." and an absolute path in /tmp/ and end up looking for the temp file in the wrong place.  This change puts the temp file under the current working directory, which should resolve the issue.

Most of the Windows test failures are due to the path separator not being "/".  The general approach I took here was to keep paths in "URL form" (ie using "/" separators) as much as possible, and only convert to native paths when we attempt to open a file.  This will allow the most consistency between different host OS.  For example, data structures that store paths still store them with "/" delimiters.  Functions that accepted paths as input and return them as outputs still use "/".

There are still a few test failures that need to be sorted out.

- config/setup/TestRoot (I hear this has already been fixed by someone else)
- middleware/basicauth/TestBrowseTemplate and middleware/templates/Test (a line endings issue that I'm still working through)

Fix failing test (windows) - simulate an error by executing stat on a filename with zero-byte in it. Fix cleanup of created files after the tests.

Distinguish between windows and linux builds

Distinguish between windows and linux builds

Ran gofmt -s, fixed some golint warnings, refactored some large functions

Minor quality improvements (closes #253)

Add tests for root.go

... I think. Submitting as PR to double-check. This change changes file mod times on the testdata to ensure they are not all the same so that the sort is predictable!

browse: Better test coverage and fix #264

Exhaustive test coverage to test the usage of sort,order and limit parameter for the browse middleware

browse: allow consecutive spaces in filenames

New core middleware, MIME.

And added tests for status code and scheme

Turns out the stuff in the test file needs to be exported so external add-ons can use them

fastcgi: Stripping PATH_INFO from SCRIPT_NAME

Conflicts:
	middleware/fastcgi/fastcgi.go

core: change to new http2 repo

The golang.org/x/net/http2 is now the official http2 repo.
It is advised to change the imports to it.