Remove buggy tramp workaround code from flymake-start-syntax-check-process

I just spent a couple of hours tracking down a bug where whenever I opened a Javascript file, Emacs added an extra blank line at the bottom.

This turned out to be down to a combination of the TRAMP workaround code inserting a newline and the fact that I didn't have jslint (or jshint, or whatever) installed, so the checking process errored out, leaving the extra newline in my buffer.

I understand the motivation, but I suggest if there's a bug in TRAMP (and maybe in any case it's fixed now?) it should be fixed in TRAMP. Since flymake.el is in Emacs, bug-emacs@gnu.org would love to know if there are bugs like this that need fixing.

This pull request removes the workaround, and includes the corresponding documentation changes, and version bump and Changes entry.