Now parses error and failure messages.
Add message output to split window.

Still need the logic code to prevent displaying a split window when already opened, as well as syntax highlighting.
Only opened message windows when one not already opened.
Allow multiple tests to be run on the same file.
Allow for tests to fail, then succeed.
Removed useless "filepath" arguments when dealing with current window.
Update a call to normal by normal!
Fixed number of arguments.

s:OpentEmptyMessageWindow() only need the height, the filepath is infered from
the current file.
Merge branch 'develop'