Add dwm_loadavg to display the average system load

Reccomendation -> Recommendations

Connman is a lightweight network manager.
With this patch basic network information like SSID, WLan signal
strength and IP can be provided to the dwm-bar.

fixing typo on CONTRIBUTING.md

For portability, sh allows the script to run on other shells set by the user. This has been tested on Bash and Posix sh and still functions using them.

add dwm_wpa.sh

Its "dwm" not "DWM"

Commits were not named due to frequency before
The script now builds, installs, and configures almost all aspects of my typical Void Linux install
A speperate script for dwm-bar configuration will be created in the future in the appropriate repository (https://github.com/joestandring/dwm-bar)

The 'SEP' contain the charachter(s) that are placed before and after a
module (respectively). For example, if SEP1="[" and SEP2="]" then each
module will be surrounded by those charachters.

Add dwm_backlight that displays the value of
xbacklight rounded to the nearest int.

- Individual functions no longer contain the square brackets to act as
seperators. These are instead included in the xsetroot command within
dwm_bar.sh itself so that they can be modified much more easily if the user desires.
- Fixed dwm_battery.sh showing a space between the level and '%' symbol
when discharging.
- Added dwm_ccurse to dwm_bar.sh. Guess I forgot that.

- Added the $IDENTIFIER value that determines if unicode or plaintext is
used for function identifiers
- Cleaned up scripts with the help of shellchecker
- Fixed dwm_status so that other drives mounted within /home are ignored
- Replaced unicode codes with actual unicode in the source. For some
reason the codes didnt work on my Void machine
- Updated readme