docs: change section title

Author: kenjis

docs/0 - install.md

@@ -11,7 +11,7 @@ If you have it installed as a phar, or othewise you will need to adjust the way
 
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-#### **IMPORTANT**:
+#### IMPORTANT: composer error
 
 If you get the following error:
 
@@ -54,7 +54,7 @@ table to store configuration options. As such, you should run the migrations.
 
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-#### **Note**:
+#### Note: migration error
 
 When you run `spark migrate --all`, if you get `Class "SQLite3" not found` error: