Reduce message from warning to just debug.

A NIDS product without a symbology block is not an error, so don't bother
warning about it.
Refactor to move
main: ucar.nc2.util.net to ucar.httpclient.
Also made ucar.httpclient be top-level
with its own pom.xml.
Reasons:
1. so we can include this code in opuls d4client
without having any other thredds dependencies.
2. part of the long term campaign to regularize
the structure of cdm.
Fixed a bug that occurred when sorting in ImprovedFileChooser.
Fixed ImprovedFileChooser sorting bug again, but better!
Merge remote-tracking branch 'remotes/origin/target-4.4.3' into 4.5.0

Conflicts:
	httpclient/src/main/java/ucar/httpclient/HTTPException.java
	httpclient/src/main/java/ucar/httpclient/HTTPSSLScheme.java
	httpclient/src/main/java/ucar/httpclient/package.html
	tdm/src/main/java/thredds/tdm/TdmRunner.java
get isLeaf() right;
IOSP tweaks