Fix integration test (shared context by accident)
Ensure the AuthenticationManager is created when needed

There was too much state really in the old implementation of
AuthenticationManagerConfiguration, and it was leading occasionally
to null pointers when method A assumed that method B had already
been called and it hadn't. This change manages to concentrate all the
references to an AuthenticationManagerBuilder into a single method
call, removoing the need for storing it at all.

Fixes gh-1556
Remove JDBC from secure-web sample

Fixes gh-1534
Merge branch '1.1.x'
Blitz some more special characters from the metric names

When MVC path matchers are used as metric keys, they can still contain
invalid characters and patterns (like asterisks). This change removes
some more special characters and also tidies up the names a bit so
no key part starts or ends with "-" (which is ugly).

Fixes gh-1528
Add /error to ignored paths for security autoconfig

Protecting /error doesn't make a great deal of sense and if it is
protected you don't get the ErrorPageFilter for the attempt at loading
it, so Tomcat renders its own HTML error page (when deployed as WAR).

Fixes gh-1548
Blitz some more special characters from the metric names

When MVC path matchers are used as metric keys, they can still contain
invalid characters and patterns (like asterisks). This change removes
some more special characters and also tidies up the names a bit so
no key part starts or ends with "-" (which is ugly).

Fixes gh-1528
Merge branch '1.1.x'
Update docs on metrics names
Merge branch '1.1.x'
Use class name not value to support non-Hibernate JPA vendors

With this change I got a simple Eclipselink version of the data-jpa
sample working. I'll push that when I get time to research it a bit more
(I needed to set up a Java agent so either that might be a problem
for our integration tests if we can't work around it).

Fixes gh-1268. Cherry picked onto master after (apparently) a failed
merge of commit ac2ab39.
Add url,user,password to LiquibaseProperties

User can set those properties (optionally) to use a different
DataSource than the default.

Fixes gh-1558
Add additional class conditions for JTA auto-configuration

Previously, JTA auto-configuration would fail with a variety of
ClassNotFoundExceptions and NoClassDefFoundErrors if it was used with
an “incomplete” classpath. This commit adds a number of classes to
@ConditionalOnClass annotations so that the auto-configuration backs
off gracefully in the absence of certain classes.

Specifically, the following now work as expected:

 - Deploying an app to a server with JTA available via JNDI when the
   app does not use transactions
 - Auto-configuration of Atomikos without JMS
 - Auto-configuration of Bitronix without JMS

Both XADataSourceAutoConfiguration and JndiDataSourceAutoConfiguration
have been updated to back off in the absence of spring-jdbc; a
dependency of DataSourceProperties which is used by both classes.

Error handling in AtomikosDependsOnBeanFactoryPostProcessor and
BitronixDependentBeanFactoryPostProcessor has been enhanced so that the
correct dependencies are established, even in the absence of JMS.

Fixes gh-1538
Merge branch '1.1.x'
Provide group in ResolvedArtifactLibrary to enable discrimination

The fix for gh-1475 introduced the use of an artifact's group to
discriminate between two libraries with the same name (artifact id)
and version. However, in the case of Gradle, a group name was not
provided for libraries that have been resolved from a repository.

This commit updates ResolvedArtifactLibrary to use the group obtained
from the underlying ResolvedArtifact as its discriminator.

Fixes gh-1543
Merge branch '1.1.x'
Document build-time property expansion using Gradle

Closes gh-1540
Merge branch '1.1.x'
Reinstate repository configuration in spring-boot-samples pom

The repository configuration is there in 1.1.x but missing in master.
This commit brings the two branches back into line.

Closes gh-1473
Polish