Update the Spring Insight documentation

The Java Buildpack requires Spring Insight version 2.0.0 or above in order to
function properly. This is not documented and this commit adds the version
requirement to the documentation.

[#74932796]
Merge branch 'cgfrost-Spring-Insight-Documentation'

[resolves #72]
Change the default Access Log pattern in Tomcat

From GitHub issue #57. The current access logging pattern isn't as useful as it
could be. The logs will often be viewed alongside with the Router logs and
should provide complementing information and not overlap with it.

[#74837854]
Merge branch 'cgfrost-master'

[resolves #71]