Update NetworkChecker to match dev_4_4
Refactor connectors to multimap
Remove synchronized from isSessionAlive
Add caching to Connector

Connector objects were being created without needed
in some instances. Since the instantiation of an
omero.clients object has high overhead, it's worth
preventing this.
Add static caching to NetworkChecker

Conflicts:
	components/insight/SRC/org/openmicroscopy/shoola/util/NetworkChecker.java
Remove ping since it doesn't check entryUnecrypted
Refactor isSessionAlive/network logic into getConnector

Since all service access calls getConnector(), all logic for
handling the checking of alive sessions and network has been
refactored into the one location. This also prevents multiple
calls.
Fix race condition on UserDetails

Most likely, the synchronized methods on OMEROGateway
were hiding this, but a race-condition during startup
allowed dsFactory.getCredentials() to return null.
Increase keep alive check to 30 seconds
Use cached Connector!
Remove all synchronization from OMEROGateway methods
fix #11090: disable Cancel All button when not needed
fix some minor typos
Stateful service cleanup in env.data

 * Remove Connector.reconnect() since it leaves services dangling
 * Remove all get*Service() methods from OMEROGateway
 * Refactor all get*Service() methods in Connector
 * Use concurrent storage for services in Connector
 * Close all stateful services as quickly as possible.
Fix concurrent modification err in Connector
Review loading of thumbnails. (see #10748)
Do not load thumbnails for image with X*Y>2k*2k (see #10748)
Fix loading of thumbnails for bird eye view and fields (see #11071)
Do not set the default for the thumbnails.
Remove commented out code.