Typewriter Mode

This update adds a restore cursor position functionality. When you open a file the
cursor will automatically jump to the position it was at when you edited the file the last
time. This lets you continue right where you left off. The feature is not enabled by default. You can enable it in the plugin's settings.

The feature is similar to the incredible Remember Cursor Position by dy-sh and loosely based on it. But it should provide a better performance, because it does not store the cursor position based on a timer, but only when the cursor actually moves (which is when the Typewriter Mode plugin runs its updates anyway).

Other minor changes include:

• Fix live update of current line highlight style setting
• Add commands to toggle/activate/deactivate the complete plugin
• Internal code restructuring
• Bug fixes