Add .clang-format file

To have any hope of achieving consistent formatting there needs to be
a standard and a mechanism for enforcing it. This is a first step in
that direction.

This format specification is intended to mimic the existing style
insofar as the current source has any consistent style. For example
the determination as to whether ref qualifiers should bind to the
type or variable name was made by trying both and seeing which
produced fewer changes. One exception is the use of tabs vs. spaces,
which was decided based on a comment by neilmacintosh [here][1].

To use clang-format with Visual Studio [download][2] and install the
clang-format plugin. In VS ctrl-r, ctrl-f formats the current line or
text selection.

[1]: https://github.com/Microsoft/GSL/issues/55
[2]: http:llvm.org/builds/

.clang-format

@@ -0,0 +1,21 @@
+ColumnLimit: 0
+
+UseTab: Never
+IndentWidth: 4
+AccessModifierOffset: -4
+NamespaceIndentation: Inner
+
+BreakBeforeBraces: Allman
+AlwaysBreakTemplateDeclarations: false
+BreakConstructorInitializersBeforeComma: true
+ConstructorInitializerAllOnOneLineOrOnePerLine: true
+AllowShortBlocksOnASingleLine: true
+AllowShortFunctionsOnASingleLine: All
+AllowShortIfStatementsOnASingleLine: true
+AllowShortLoopsOnASingleLine: true
+
+PointerAlignment: Left
+AlignConsecutiveAssignments: false
+AlignTrailingComments: false
+
+SpaceAfterCStyleCast: true