style: switch to requiring 4 spaces of indentation

Author: zbeekman

.editorconfig

@@ -10,14 +10,14 @@ root = true
 
 [*.{f90,F90}]
 indent_style = space
-indent_size = 2
+indent_size = 4
 trim_trailing_whitespace = true
 max_line_length = 132
 insert_final_newline = true
 
 [{CMakeLists.txt, *.cmake}]
 indent_style = space
-indent_size = 2
+indent_size = 4
 trim_trailing_whitespace = true
 max_line_length = 132
 insert_final_newline = true
@@ -38,7 +38,7 @@ insert_final_newline = true
 
 [*.sh]
 indent_style = space
-indent_size = 2
+indent_size = 4
 trim_trailing_whitespace = true
 max_line_length = 132
 insert_final_newline = true

STYLE_GUIDE.md

@@ -25,7 +25,7 @@ focus on the semantics of the proposed changes rather than style and formatting.
 * __Trailing whitespace__: All trailing whitespace must be removed
 * __End of File (EOF)__: The file must end in a single new-line character
 * __Line length__: __132__: The Fortran 90 (and later) standard mandates lines be no longer than 132 characters
-* __Indentation__: __Two (2) spaces__ for all control constructs, line continuations, etc.
+* __Indentation__: __Four (4) spaces__ for all control constructs, line continuations, etc.
 * __Line ending character__: __Native__: Git will convert line endings to `\n` (Unix style) on commit, and will checkout files with native line endings
 
 ## Variable naming