Added .ant-targets* to .gitignore, so that target caching does not show as a change.
Updated GitHub project url in README to be 'https' instead of outdated 'http'.

Note that, at the time of this commit, GitHub's policy is to have https only
connections; thus this won't have an effect on which protocol a browser following
this link will actually use.
Updated the snakeyaml version in build.properties to match what ivy retrieves.

The snakeyaml file listed in build.properties for the property 'yaml.jar'
was 'snakeyaml-1.6.jar'. However, ivy retrieves 'snakeyaml-1.12.jar' as a
dependency. The version mismatch was causing the build to fail.
Changed class specification to its fully qualified classname in testng-ant.xml

Running the ant target 'test-ant' would fail when the class specified in
testng-ant.xml, 'NoPackageTest', could not be found.
Fixed dependencies for 4 targets in build.xml

The targets 'tests', 'test-ant', and 'javadocs' all fail without running the
target 'build' first, since they rely on the testng.jar to run. The target
'build' has been added as a dependency to each of these.

The target 'tests' had previously listed 'compile' as a dependency, but this
has been removed since 'build' covers this already.

Another target, 'create-jar', requires the directory target/classes in order
not to fail, and requires the testng classes to make a meaningful jar. It works
properly once the target 'compile' has been run, so 'compile' is now added to
its dependency list.