CC-2518: Auto install script for manual install

- install dir is renamed to install_minimal
- virtualenv command is moved to install script.
- need more work on install_full part

install_minimal/DoctrineMigrations/migrations.xml

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<doctrine-migrations xmlns="http://doctrine-project.org/schemas/migrations/configuration"
+      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+      xsi:schemaLocation="http://doctrine-project.org/schemas/migrations/configuration
+                    http://doctrine-project.org/schemas/migrations/configuration.xsd">
+
+    <name>Airtime 1.9.0 Database Upgrade</name>
+
+    <migrations-namespace>DoctrineMigrations</migrations-namespace>
+
+    <table name="doctrine_migration_versions" />
+
+    <migrations-directory>./</migrations-directory>
+
+</doctrine-migrations>