add editorconfig for consistent indent/trailing space

Author: summivox

.editorconfig

@@ -0,0 +1,14 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+indent_style = space
+
+[Makefile]
+indent_style = tab
+
+[.travis.yml]
+indent_size = 4

src/.editorconfig

@@ -0,0 +1,4 @@
+# C/C++
+[*.{cpp,hpp,cc,cxx,c,h}]
+indent_style = space
+indent_size = 2