Add paragraph alignment setting (justify/left/center/right) (#191)

## Summary

* **What is the goal of this PR?** 

Add a new user setting for paragraph alignment, instead of hard-coding
full justification.

* **What changes are included?**

One new line in the settings screen, with 4 options
(justify/left/center/right). Default is justified since that's what it
was already. I personally only wanted to disable justification and use
"left", but I included the other options for completeness since they
were already supported.

## Additional Context

Tested on my X4 and looks as expected for each alignment.

Co-authored-by: Maeve Andrews <maeve@git.mail.maeveandrews.com>

src/CrossPointSettings.cpp

@@ -12,7 +12,7 @@ CrossPointSettings CrossPointSettings::instance;
 namespace {
 constexpr uint8_t SETTINGS_FILE_VERSION = 1;
 // Increment this when adding new persisted settings fields
-constexpr uint8_t SETTINGS_COUNT = 10;
+constexpr uint8_t SETTINGS_COUNT = 11;
 constexpr char SETTINGS_FILE[] = "/.crosspoint/settings.bin";
 }  // namespace
 
@@ -37,6 +37,7 @@ bool CrossPointSettings::saveToFile() const {
   serialization::writePod(outputFile, fontFamily);
   serialization::writePod(outputFile, fontSize);
   serialization::writePod(outputFile, lineSpacing);
+  serialization::writePod(outputFile, paragraphAlignment);
   outputFile.close();
 
   Serial.printf("[%lu] [CPS] Settings saved to file\n", millis());
@@ -83,6 +84,8 @@ bool CrossPointSettings::loadFromFile() {
     if (++settingsRead >= fileSettingsCount) break;
     serialization::readPod(inputFile, lineSpacing);
     if (++settingsRead >= fileSettingsCount) break;
+    serialization::readPod(inputFile, paragraphAlignment);
+    if (++settingsRead >= fileSettingsCount) break;
   } while (false);
 
   inputFile.close();