doc: fix all headings to use title case

While we hoped to make the headings consistent over time while doing
other edits, we should instead just make the squirrels happy and do them
all at once or they'll likely never be made consistent.

A python script was used to find the headings, and then a call to
https://pypi.org/project/titlecase to transform the title.  A visual
inspection was used to tweak a few unexpected resulting titles.

Signed-off-by: David B. Kinder <david.b.kinder@intel.com>

doc/faq.rst

@@ -9,9 +9,8 @@ Here are some frequently asked questions about the ACRN project.
    :local:
    :backlinks: entry
 
-------
 
-What hardware does ACRN support?
+What Hardware Does ACRN Support?
 ********************************
 
 ACRN runs on Intel boards, as documented in
@@ -19,7 +18,7 @@ our :ref:`hardware` documentation.
 
 .. _config_32GB_memory:
 
-How do I configure ACRN's memory size?
+How Do I Configure ACRN's Memory Size?
 **************************************
 
 It's important that the ACRN configuration settings are aligned with the
@@ -53,7 +52,7 @@ the ACRN Service VM with the 32G memory size.
 
 #. Then continue building the ACRN Service VM as usual.
 
-How to modify the default display output for a User VM?
+How to Modify the Default Display Output for a User VM?
 *******************************************************
 
 Apollo Lake HW has three pipes and each pipe can have three or four planes which
@@ -98,7 +97,7 @@ these parameters:
    intentional, and the driver will enforce this if the parameters do not
    do this.
 
-Why does ACRN need to know how much RAM the system has?
+Why Does ACRN Need to Know How Much RAM the System Has?
 *******************************************************
 
 Configuring ACRN at compile time with the system RAM size is a tradeoff between