Improve SSL / TLS support

[dhartford]

Find way to improve SSL / TLS support when using HTTPS endpoint.

Example usecase, with a Thawte SSL cert: change url from http://localhost:8080 to an HTTPS location, preview and get error:

Cannot access "https://.....": : sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

it.francescocorti.kettle.cmisinput.CmisInputMeta.getFields(Unknown Source)
it.francescocorti.kettle.cmisinput.CmisInput.processRow(Unknown Source)
org.pentaho.di.trans.step.RunThread.run(RunThread.java:60)

Caused by: org.apache.chemistry.opencmis.commons.exceptions.CmisConnectionException: Cannot access "https://....": sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
org.apache.chemistry.opencmis.client.bindings.spi.http.DefaultHttpInvoker.invoke(DefaultHttpInvoker.java:230)
org.apache.chemistry.opencmis.client.bindings.spi.http.DefaultHttpInvoker.invokeGET(DefaultHttpInvoker.java:57)
org.apache.chemistry.opencmis.client.bindings.spi.atompub.AbstractAtomPubService.read(AbstractAtomPubService.java:630)
org.apache.chemistry.opencmis.client.bindings.spi.atompub.AbstractAtomPubService.getRepositoriesInternal(AbstractAtomPubService.java:797)
org.apache.chemistry.opencmis.client.bindings.spi.atompub.RepositoryServiceImpl.getRepositoryInfos(RepositoryServiceImpl.java:65)
org.apache.chemistry.opencmis.client.bindings.impl.RepositoryServiceImpl.getRepositoryInfos(RepositoryServiceImpl.java:90)
org.apache.chemistry.opencmis.client.runtime.SessionFactoryImpl.getRepositories(SessionFactoryImpl.java:135)
org.apache.chemistry.opencmis.client.runtime.SessionFactoryImpl.getRepositories(SessionFactoryImpl.java:112)
it.francescocorti.kettle.cmisinput.CmisSessionFactory.getNewSession(Unknown Source)
it.francescocorti.kettle.cmisinput.CmisSessionFactory.getSession(Unknown Source)
it.francescocorti.kettle.cmisinput.CmisInputMeta.getSession(Unknown Source)

caused by: javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed