Coding style related changes (#653)

* Add .astylerc with the core coding standard

* Added pre-commit git hook

The hook currently only checks code format using
astyle and will not permit commits which cause
astyle to change the contents of any source file
in the commit.
This is useful to have automatic coding standard
verification done without having to wait for
Jenkins to react to a pull request.

Installation:
Linux:
ln -s ../../tools/hooks/pre-commit.sh .git/hooks/pre-commit
Windows:
copy tools\hooks\pre-commit.sh .git\hooks\pre-commit

* Added editorconfig and updated gitattributes

Unix style line endings are now default.

* Resolved doxygen warning

.editorconfig

@@ -0,0 +1,19 @@
+# EditorConfig is awesome: http://EditorConfig.org
+
+# top-most EditorConfig file
+root = true
+
+# Unix-style newlines with UTF-8 encoding for every file
+[*]
+end_of_line = lf
+charset = utf-8
+
+# For all source code
+[*.{c,cpp,h,ino}]
+insert_final_newline = true
+indent_style = tab
+indent_size = 2
+
+# Tab indentation also for makefiles
+[Makefile]
+indent_style = tab