Add support for parsing column numbers in Visual Studio messages
* lisp/progmodes/compile.el (compilation-error-regexp-alist-alist):
Extend regular expression to match optional column numbers.
*
test/lisp/progmodes/compile-tests.el (compile-tests--test-regexps-data):
Add a test.
* test/lisp/progmodes/compile-tests.el (compile-test-error-regexps):
Update the total number of compilation errors in a test.
* etc/compilation.txt: Update compilation.txt with the newly supported
message format.
* etc/NEWS: Advertise the feature.