Enable splash screen with a tip of the day. Closes #259

Only one tip of the day right now.
Stub out remaining python API functions for D
Implement python saveNetwork (needs GUI listener though)
Update release notes.
Start centralizing test resource paths.
Add getOptionalInput() to Module
CMake code for centralized unit test resource path
Continue centralizing paths
All unit test paths centralized. Works on Windows
Update ignore.
Rearrange CMake commands
Update Mac default path.
Fix for non-testing build.
Update default path and message.
Remove defaults.
Local windows path fix--temporary.
Merge branch 'master' into trisurf

Conflicts:
	src/Core/Algorithms/DataIO/Tests/ReadMatrixTests.cc
Backtrack spire reference.
Merge branch 'triSurfDan' into trisurf