List boolean capability map values

@jhovell @klieber

With this pull request you are able to provide chromeOptions whose value are a boolean or a list, like so
```xml
<plugin>
  <groupId>com.github.searls</groupId>
  <artifactId>jasmine-maven-plugin</artifactId>
  <version>1.3.1.5-SNAPSHOT</version>
  <executions>
    <execution>
      <id>Run jasmine tests</id>
      <phase>test</phase>
      <goals>
        <goal>test</goal>
      </goals>
    </execution>
  </executions>
  <configuration>
    <webDriverClassName>org.openqa.selenium.chrome.ChromeDriver</webDriverClassName>
    <webDriverCapabilities>
      <capability>
        <name>browserName</name>
        <value>chrome</value>
      </capability>
      <capability>
        <name>chromeOptions</name>
        <map>
          <args>[crash-test,no-sandbox]</args>
          <binary>/usr/bin/google-chrome</binary>
          <detach>true</detach>
        </map>
      </capability>
    </webDriverCapabilities>
  </configuration>
</plugin>
```

I don't particularly like some of the things I had to do to get this to work. Capability is a bean and shouldn't contain this logic for setting the map like this, however everything read in the pom was being treated as a string. I'm not that familiar with AbstractMojo. Is there a way you can have it evaluate values with square brackets as a list of strings, and true / false as booleans?