Merge pull request #878 from jikuja/fixes_for_v1.4.5

FIXED: offline mode
don't access static variables via instances
use guava's HTTP header constants instead of strings
Issue 286 - Show Default Pack Mods in Edit Dialog

Signed-off-by: Ryan OMeara <romeara@blackducksoftware.com>
Issue 286 - Restore compatibility with Java6

Fix use of Java7 APIs, as the launcher is still supporting Java6.
Additionally switch the font tag used to color the additional data to
use rgb, as testing shows that while Java7 recognized the "orange"
keyword, Java6 does not
update shadow gradle plugin to latest version for compat fixes for latest gradle version
Issue 880 - Made texture pack mod lists contain version

Signed-off-by: Ryan OMeara <romeara@blackducksoftware.com>
Issue 880 - Use MC version instead of mod version

Signed-off-by: Ryan OMeara <romeara@blackducksoftware.com>
Merge pull request #882 from romeara/dev/feature/show-mod-pack-default

Issue 286 - Show Default Pack Mods in Edit Dialog
Merge pull request #883 from romeara/dev/feature/texturepack-list-show-version

Issue 880 - Made texture pack mod lists contain version
Added ComparableVersion from maven-artifact
Added support java versioning
Added more test for ComparableVersion

 * Test java and MC version schemes
 * use junit4 style
Refactored JavaInfo to use ComparableVersion

 * Changed AdvancedOptionsDialog to use new sorting method
Added mockity, powermock, tests
Added comparison function in Java(Info|Version) and ComparableVersion

 * Added tests for new functions
JavaInfo: use static factory method

 * Added caching for JavaInfo objects
 * Minor cleanups
Added null checks
Refactored various classes to use new Java(Info|Version) comparison
Cleanup
update dependencies, gradle wrapper
add jsr 305 for @nonnull annotations