Output killjava.sh to console

Previously, the killjava.sh script output was directed to a file.  This
worked previously with the crashlogs command to ensure that users could
see what had gone wrong.  With the removal of the crashlogs command,
this command no longer worked properly.  This change updates the script
to output to the console instead, where the output will be picked up by
loggregator.

[#57139852][resolves #79]
Merge 57139852-oom-loggregator to master

[Completes #57139852]
Custom Download CA Certificates

Previously, when a download was done using the DownloadCache using
HTTPS, it was assumed that the SSL certificate presented by the server
could be validated with the CA store packaged with OpenSSL.  This
didn't work for servers that included self-signed, or non-standard CA
-based certificates.  This change updates the DownloadCache to allow a
user to present a collection of additional CA certificates.  By
creating a /resources/ca_certs directory and placing the certificates
(in PEM format) within it, the DownloadCache will use the provided
certificates during verification.
Merge branch 'ca-certs'
Use ca_file instead of ca_path

The previous implementation of CA certs during download used the
ca_path HTTP option.  It appears that this does not work with the
latest versions of OpenSSL, and so it was changed to  use ca_file
instead.  This change also means that all certificates should be
placed in a /resources/ca_certs.pem file instead of the previous
directory strategy.
Merge branch 'ca-certs'
Tomcat Redis Session Replication

When the Tomcat Redis sub-component detects a service with a name, label, or
tag that has `session-replication` as a substring but both 'host' and
'hostname' as credentials it will fail to use the service. This commit changes
the service detection logic to require at least one credential from a group
instead of exactly one credential from a group. It is up to the individual
containers to handle the credentials provided. In the case of the Tomcat Redis
sub-component 'hostname' will win but this is not documented and users should
not rely on that behaviour in the instances where both 'host' and 'hostname'
are provided with different values.

[#80362118]
Merge branch 'cgfrost-80362118-session-replication'

[resolves #102][resolves #104]
Update access logging documentation

Minor changes to the documentation to make it clearer what the configuration
options and values are for access logging with Tomcat.

[#80898232]
Merge branch 'cgfrost-80898232-access-logging-doc'
Document excluded JAVA_OPTS memory configurations

Any environment variables or config in the 'config/java_opts.yml' file that
attempts to set a memory option will cause deployment to fail. This is not
documented and this commit adds the relavent documentation.

[#79949526]
Merge branch 'cgfrost-79949526-Java-opts-docs'
Add SSL debugging

Previously there was no good way to view the SSL configuration that
was eventually negotiated.  This change ensures that that information
is logged at DEBUG.
More defensive

Guess I should test before pushing.  This change makes the SSL debug
logging a lot more defensive.
Ruby upgrade

This change upgrades the versions of Ruby that the project is built
and tested against.
Ruby Upgrade

This change upgrade the version of Ruby used by the buildpack
Document memory settings

This commit adds more details documentation about the memory settings that can
and can not be supplied to the Java buildpack and if the setting is likely to
effect the memory weighting in relation to the total memory provided to an
application.

[#78798560]
Polishing

This change polishes up the submitted documentation.
Merge branch 'cgfrost-78798560-Memory-Java-opts'
Remove the Download cache timeout

This commit removes the timeout limit for the download cache, instead
falling back to the Ruby default of 60 seconds.

[#83473194]