docs: Match Single Blank Line Above and Below A Title

Signed-off-by: Yifei Ding <yifeiding@protonmail.com>

docs/HallFilamentWidthSensor.md

@@ -5,6 +5,7 @@ This document describes Filament Width Sensor host module. Hardware used for dev
 [Hall based filament width sensor assembly video](https://www.youtube.com/watch?v=TDO9tME8vp4)
 
 ## How does it work?
+
 Sensor generates two analog output based on calculated filament width. Sum of output voltage always equals to detected filament width . Host module monitors voltage changes and adjusts extrusion multiplier. I use aux2 connector on ramps-like board analog11 and analog12 pins. You can use different pins and differenr boards
 
 ## Configuration
@@ -71,6 +72,7 @@ Sensor generates two analog output based on calculated filament width. Sum of ou
 
 
 ## Commands
+
 **QUERY_FILAMENT_WIDTH** - Return the current measured filament width as result
 
 **RESET_FILAMENT_WIDTH_SENSOR** – Clear all sensor readings. Can be used after filament change.
@@ -107,6 +109,7 @@ Sensor generates two analog output based on calculated filament width. Sum of ou
     index: 1
 
 ## Calibration procedure
+
 Insert first  calibration rod (1.5 mm size) get first  raw sensor value
 
 To get raw sensor value you can use menu item or  **QUERY_RAW_FILAMENT_WIDTH** command in terminal
@@ -116,9 +119,11 @@ Insert second calibration rod (2.0 mm size) get second raw sensor value
 Save raw values in config
 
 ## How to enable sensor
+
 After power on by default sensor disabled.
 Enable sensor in start g-code by command **ENABLE_FILAMENT_WIDTH_SENSOR** or change enable parameter in config
 
 ## Logging
+
 After power on by default diameter Logging disabled.
 Data to log added on every measurement interval (10 mm by default)

docs/Resonance_Compensation.md

@@ -447,7 +447,6 @@ No, `input_shaper` feature has pretty much no impact on the print times by
 itself. However, the value of `max_accel` certainly does (tuning of this
 parameter described in [this section](#selecting-max_accel)).
 
-
 ## Technical details
 
 ### Input shapers

docs/Status_Reference.md

@@ -396,6 +396,7 @@ object is available if z_tilt is defined):
   successfully.
 
 ## neopixel / dotstar
+
 The following information is available for each `[neopixel led_name]` and
 `[dotstar led_name]` defined in printer.cfg:
 - `color_data`:  An array of objects, with each object containing the RGBW

docs/TSL1401CL_Filament_Width_Sensor.md

@@ -3,9 +3,11 @@
 This document describes Filament Width Sensor host module. Hardware used for developing this host module is based on TSL1401CL linear sensor array but it can work with any sensor array that has analog output. You can find designs at [thingiverse.com](https://www.thingiverse.com/search?q=filament%20width%20sensor)
 
 ## How does it work?
+
 Sensor generates analog output based on calculated filament width. Output voltage always equals to detected filament width (Ex. 1.65v, 1.70v, 3.0v). Host module monitors voltage changes and adjusts extrusion multiplier.
 
 ## Configuration
+
     [tsl1401cl_filament_width_sensor]
     pin: analog5
     # Analog input pin for sensor output on Ramps board
@@ -27,6 +29,7 @@ Sensor generates analog output based on calculated filament width. Output voltag
 Sensor readings done with 10 mm intervals by default. If necessary you are free to change this setting by editing ***MEASUREMENT_INTERVAL_MM*** parameter in **filament_width_sensor.py** file.
 
 ## Commands
+
 **QUERY_FILAMENT_WIDTH** - Return the current measured filament width as result
 **RESET_FILAMENT_WIDTH_SENSOR** – Clear all sensor readings. Can be used after filament change.
 **DISABLE_FILAMENT_WIDTH_SENSOR** – Turn off the filament width sensor and stop using it to do flow control

docs/Using_PWM_Tools.md

@@ -3,8 +3,8 @@
 This document describes how to setup a PWM-controlled laser or spindle
 using `output_pin` and some macros.
 
-
 ## How does it work?
+
 With re-purposing the printhead's fan pwm output, you can control
 lasers or spindles.
 This is useful if you use switchable print heads, for example

docs/skew_correction.md

@@ -7,6 +7,7 @@ first use mechanical means to get your printer as square as possible prior
 to applying software based correction.
 
 ## Print a Calibration Object
+
 The first step in correcting skew is to print a
 [calibration object](https://www.thingiverse.com/thing:2563185/files)
 along the plane you want to correct.  There is also a
@@ -19,6 +20,7 @@ do this by either removing the [skew_correction] module from printer.cfg
 or by issuing a `SET_SKEW CLEAR=1` gcode.
 
 ## Take your measurements
+
 The [skew_correcton] module requires 3 measurements for each plane you want
 to correct; the length from Corner A to Corner C, the length from Corner B
 to Corner D, and the length from corner A to corner D.  When measuring length
@@ -28,6 +30,7 @@ AD do not include the flats on the corners that some test objects provide.
 
 ## Configure your skew
 Make sure [skew_correction] is in printer.cfg.  You may now use the `SET_SKEW`
+
 gcode to configure skew_correcton.  For example, if your measured lengths
 along XY are as follows:
 ```
@@ -72,6 +75,7 @@ After removing a profile you will be prompted to issue a `SAVE_CONFIG` to
 make this change persist.
 
 ## Verifying your correction
+
 After skew_correction has been configured you may reprint the calibration
 part with correction enabled.  Use the following gcode to check your
 skew on each plane.  The results should be lower than those reported via