use gnu indent to enforce coding style and adapt source

- indent options are listed in ./.indent.pro
 - use test case to run indent

.indent.pro

@@ -0,0 +1,33 @@
+--blank-lines-after-declarations
+--blank-lines-after-procedures
+--blank-lines-after-commas
+--break-before-boolean-operator
+--honour-newlines
+--braces-on-if-line
+--braces-on-struct-decl-line
+--comment-indentation33
+--declaration-comment-column33
+--no-comment-delimiters-on-blank-lines
+--cuddle-else
+--continuation-indentation4
+--case-indentation4
+--line-comments-indentation0
+--declaration-indentation16
+--dont-format-first-column-comments
+--indent-level4
+--parameter-indentation0
+--line-length80
+--continue-at-parentheses
+--no-space-after-function-call-names
+--no-space-after-parentheses
+--dont-break-procedure-type
+--space-after-if
+--space-after-for
+--space-after-while
+--no-space-after-casts
+--swallow-optional-blank-lines
+--dont-format-comments
+--else-endif-column33
+--space-special-semicolon
+--indent-label1
+--no-tabs