Update root-level README and reorganize sources

In an effort to mitigate questions from new, inexperienced users on how
to import data into Fight Club 5e, I rewrote and reorganized the
root-level README file to include detailed instructions on how to
compile their own compendiums using the sources found within this
repository. Some existing data, such as how to create your own
collection file, was moved into other READMEs under the Collections and
Sources directories.

I also took some liberty in reorganizing the directory structure of this
repository and renamed some of the top-level directories. In my view,
having sources under the "FightClub5eXML" folder didn't make a lot of
sense, so I moved those sources into the top-level "Sources" folder. I
made sure to update all of the collection files, along with the
"travis.yml" config file, to properly point to the correct folders.

Finally, while updating the "travis.yml" config file, I changed the
output folder of those build compendiums to be under a top-level
"Compendiums" folder. This folder is ignored by git.

Sources/PlaneShift/backgrounds-psi.xml

@@ -0,0 +1,20 @@
+<?xml version='1.0' encoding='utf-8'?>
+<compendium version="5" auto_indent="NO">
+    <background>
+      <name>Inquisitor</name>
+    <proficiency>Investigation, Religion</proficiency>
+    <trait>
+        <name>Description</name>
+      <text>Historically, inquisitors were cathar detectives who investigated crimes both mundane and supernatural. They were known for traveling to remote parishes plagued by unexplained murders, and for exposing werewolves living among normal humans. During Avacyn's absence, when the archangel was trapped within the demonic prison known as the Helvault, the inquisitors led a series of brutal forays into Kessig and the Gavony Moorland. They executed suspected lycanthropes with little or no proof, and punished accused heretics in unsanctioned trials. With Avacyn's madness, this savage form of inquisition has become the norm, and inquisitors who still pry into dark mysteries have become a minority.
+• Skill Proficiencies: Investigation, Religion
+• Tool Proficiencies: Thieves' tools, one type of artisan's tools
+• Equipment: A holy symbol, a set of traveler's clothes, and a belt pouch containing 15 gp
+Source: Plane Shift: Innistrad p. 12</text>
+      </trait>
+    <trait>
+        <name>Feature: Legal Authority</name>
+      <text>As an inquisitor of the church, you have the authority to arrest criminals. In the absence of other authorities, you are authorized to pass judgement and even carry out sentencing. If you abuse this power, however, your superiors in the church might strip it from you.
+</text>
+      </trait>
+    </background>
+  </compendium>