Ignore text nodes when parsing XMLAnnotation's value

This fixes an error parsing Modulo annotations
(e.g. FLIM-modulo-sample.ome.tiff) in Matlab.
Fix tiled TIFF saving when partial tiles will be used

If the image width and/or height are not multiples of the tile
dimensions, then the last tile in each row or column will be smaller
than the others.  This commit prevents an exception when that is the
case.
Restrict direct tile copying to single-tile images
Switch from net.imagej:ij to gov.nih.imagej:imagej

This prevents an indirect dependency on maven.imagej.net.
Updating TILL Photonics website link
Merge pull request #877 from hflynn/till-photonics-link

Updating TILL Photonics website link
Merge pull request #873 from melissalinkert/maven-ij

Switch from net.imagej:ij to gov.nih.imagej:imagej
Merge pull request #867 from melissalinkert/rebased/dev_5_0/xmlannotation-parsing

Ignore text nodes when parsing XMLAnnotation's value (rebased onto dev_5_0)
Merge pull request #871 from melissalinkert/tile-export

Fix tiled TIFF reading and writing