Update clang-format configuration

Summary:
Update clang-format configuration:
- Don't align escaped new lines in macro definitions
- Auto-detect "bin packing" for parameters
- Set line length to 100 characters
- Don't reorder include directives.
- Automatically add comments like `}  // namespace foo`

Test Plan: Jenkins: skip

Reviewers: sergei, timur

Reviewed By: sergei, timur

Subscribers: ybase

Differential Revision: https://phabricator.dev.yugabyte.com/D7698

.clang-format

@@ -10,7 +10,7 @@ AccessModifierOffset: -1
 AlignAfterOpenBracket: AlwaysBreak
 AlignConsecutiveAssignments: false
 AlignConsecutiveDeclarations: false
-AlignEscapedNewlinesLeft: true
+AlignEscapedNewlines: DontAlign
 AlignOperands:   true
 AlignTrailingComments: true
 AllowAllParametersOfDeclarationOnNextLine: true
@@ -52,7 +52,7 @@ ContinuationIndentWidth: 4
 Cpp11BracedListStyle: true
 DerivePointerAlignment: true
 DisableFormat:   false
-ExperimentalAutoDetectBinPacking: false
+ExperimentalAutoDetectBinPacking: true
 ForEachMacros:   [ foreach, Q_FOREACH, BOOST_FOREACH ]
 IncludeCategories:
   - Regex:           '^<.*\.h>'
@@ -83,7 +83,7 @@ PenaltyExcessCharacter: 1000000
 PenaltyReturnTypeOnItsOwnLine: 200
 PointerAlignment: Left
 ReflowComments:  true
-SortIncludes:    true
+SortIncludes:    false
 SpaceAfterCStyleCast: false
 SpaceBeforeAssignmentOperators: true
 SpaceBeforeParens: ControlStatements
@@ -97,4 +97,6 @@ SpacesInSquareBrackets: false
 Standard:        Auto
 TabWidth:        8
 UseTab:          Never
+ColumnLimit: 100
+FixNamespaceComments: true
 ...