Added some text to the coding standard about variable names.

bacnet-stack/doc/code-standard.txt

@@ -9,6 +9,19 @@ to the code regardless of the authors preferred style.  You may certainly
 adjust the code to your preferred style using an indent tool.  We use the
 script indent.sh to adjust all the .c and .h files.
 
+For variable names, separate words within the variables by underscores.
+Do not use capital letters as separators. Consider how much harder
+IcantReadThis is on the eyes versus I_can_read_this.
+
+Variable and function names are defined with the first words being
+descriptive of broad ideas, and later words narrowing down to specifics.
+For instance: Universe_Galaxy_System_Planet. Consider the following names:
+Timer_0_Data, Timer_0_Overflow, and Timer_0_Capture. This convention
+quickly narrows variables to particular segments of the program.
+Never assume that a verb must be first, as often seen when naming functions.
+Open_Serial_Port and Close_Serial_Port do a much poorer job of grouping
+than the better alternative of Serial_Port_Open and Serial_Port_Close.
+
 Don't use C++-style comments (comments beginning with "//" and running
 to the end of the line) for modules that are written in C.  The module
 may run through C rather than C++ compilers, and not all C compilers