Use strings for log file locations
Merge pull request #764 from lexware/master

Use strings for log file locations
WIP: Add proper installation location checking

 * Moved installation location checking from InstallDirectoryDialog.java
   to new file.

 * minor edits
   * ChooseDir.java: use logDebug
   * InstallDirectoryDialog.java: removed focuslistener and do not allow
   use x to close dialog => full control for installation path saving
WIP:

 * LaunchFrame.java: document & todo
 * CheckInstallPath.java: new test
 * InstallDirectoryDialog.java, OptionsPane.java: TODOs for fixes
WIP: LaunchFrame is nagging now
WIP

 * fix build
 * reordered ErrorUtils
 * added proof-of-consept ErrorUtils.tossErrorSkip
 * changed LaunchFrame to use new tossErrorSkip
 * added TODOs
WIP:

 * implement new simple boolean Setting getter/setter
   TODO: add namespaces and function to clear all Settings in namespace
 * do not show log creation error at first run
 * proof-of-concept code:
   * LaunchFrame calls CheckInstallPath() to check current installation
     directory, shows dialog and saves Warning skip setting if needed
     TODO: CheckInstallPath must return name of the setting if
     warning/error is skippable
 * Cleaned messages in CheckInstallPath()
WIP

 * partially implement namespace for CheckInstallPath
 * CheckInstallPath now contains instance variable setting for
   indicating which setting can be used to skip current Warn/Error