#205 - recursive monkey-patching bug

[SebastianMC]

Fix for #205 - recursive FileExplorer patching bug

• introduced explicit unpatch (if patched) -> patch cycle
• patching every time when switching the plugin state to active is required because the FileExplorer can get into some inconsistent states, and refreshing the patch fixes potential issues. Inconsistent state of FIleExplorer typically is a result of other plugins which don't handle gracefully the Obsidian deferred views, introduced with Obsidian 1.7.x (e.g. some plugins which haven't been updated to accommodate to newer versions of Obsidian, yet still usable)