JBDS-3152 - Cheatsheet crashes silently when they need to open files
JBIDE-18381 : better lazy initialization of properties

Signed-off-by: Fred Bricon <fbricon@gmail.com>
JBIDE-18411 - bad parsing, assuming a dot and suffix in url
JBIDE-18411 - added unit test
JBIDE-18412 - aggressive caching for stacks
JBIDE-18412 - further fallback and exception handling
JBDS-3159 Usage dialog is not displayed for user after initial install