Strip tabs and trailing white spaces, and fix end of files (#748)

* format: Strip trailing whitespaces

We want to get rid of trailing whitespaces completly as they make just git
noice. Much better to start using automated tools to get rid of them once and
not getting them back again. This way git history will be cleaner and review
easier.

Commit was generated with:

    pre-commit run --all-files trailing-whitespace

* format: Files should have exactly one new line end of them

It is good practice that every file has one new line. It is not now days so
mandatory but it also is not nice if file has lot of newlines end of it. We will
use pre-commit which takes automatically care about this so let's fix all.

Commit was generated with:

    pre-commit run --all-files end-of-file-fixer

* format: Convert tabs to spaces

Project mostly use spaces over tabs. When mixing tabs and spaces this usually
makes formatting issues and also when changing those in commits it will make lot
of git noise. We will force spaces most of the time and use pre-commit to fix.

Commit was generated with:

    pre-commit run --all-files remove-tabs

---------

Co-authored-by: Kari Argillander <kari.argillander@fidelix.com>

doc/README.developer

@@ -40,8 +40,8 @@ Adding additional services is a matter of adding the encoding and decoding for
 the service into/from meaningful data, and I like to add unit testing, a demo
 handler and send function, as well as a demo command line example.
 
-For each service that you add to your project or makefile, you will need to 
-add a handler and possibly a sending function.  There are example handlers 
+For each service that you add to your project or makefile, you will need to
+add a handler and possibly a sending function.  There are example handlers
 and send functions for all the services that the stack supports:
 
     * demo/handler/h_alarm_ack.c - Alarm ACK service handler example
@@ -121,7 +121,7 @@ example object files in the BACnet stack include:
     * demo/object/lsp.c - life safety point object demo
     * demo/object/mso.c - multi-step output object demo
 
-The BACnet stack includes a number of core files that handle the service 
+The BACnet stack includes a number of core files that handle the service
 packets that come in from the datalink layer. The core files include:
 
     * apdu.c - handles dispatching the services to the proper handlers
@@ -134,11 +134,11 @@ packets that come in from the datalink layer. The core files include:
     * demo/handler/h_npdu.c - handles dispatching of the network message
             to the apdu dispatcher.
 
-The DataLink Layer controls orderly access to the physical medium. 
-The stack currently supports one datalink layer at a time, and uses a 
-macro defined in config.h or your makefile/project to choose the macro 
-functions defined in datalink.h. The following files are used for the 
-datalink handling in this BACnet stack, and may have to be developed for 
+The DataLink Layer controls orderly access to the physical medium.
+The stack currently supports one datalink layer at a time, and uses a
+macro defined in config.h or your makefile/project to choose the macro
+functions defined in datalink.h. The following files are used for the
+datalink handling in this BACnet stack, and may have to be developed for
 your particular hardware:
 
     * bip.c - BACnet/IP functionality - depends on bip_init.c in port/xx
@@ -149,15 +149,15 @@ your particular hardware:
     * arcnet.c - ARCNET datalink layer functionality, in port/xx
     * ethernet.c - BACnet Ethernet datalink layer functionality, in port/xx
 
-There are a dozen demonstration applications in the demo directory, 
-along with many demonstation objects and handlers. All the demos accept 
-command line options and have been tested under Win32 and Linux. 
-There is a makefile in the respective demo directory for Linux and 
-for Borland C++ compilers, and a master makefile at the root level 
+There are a dozen demonstration applications in the demo directory,
+along with many demonstation objects and handlers. All the demos accept
+command line options and have been tested under Win32 and Linux.
+There is a makefile in the respective demo directory for Linux and
+for Borland C++ compilers, and a master makefile at the root level
 (Makefile=Linux, makefile.b32=Borland).
 
-The simplest demonstration is to run demo/server/bacserv on one PC (or 
-virtual PC), and run the other client demonstration applications one 
-at time on another PC (or virtual PC). Monitor the network communcations 
-using Wireshark protocol analyzer, or test the BACnet server using 
+The simplest demonstration is to run demo/server/bacserv on one PC (or
+virtual PC), and run the other client demonstration applications one
+at time on another PC (or virtual PC). Monitor the network communcations
+using Wireshark protocol analyzer, or test the BACnet server using
 BACnet Visual Test Shell VTS3.