returns 0 if key was not found, returns 1 if key was deleted
[success, value], success true if value was in storage and read, value is the read string
write a value with to the local storage of the browser with the class specific key (this.key)
{string} string to write to the local storage of the browser
Base class to manage writing and reading to and from the local storage of the browser. The concept is to write and read info from a key, each class has a fixed key. This avoids knowing the key and misspelling it and creating multiple instances in the local storage. Read and writes are implemented in this class. The information is processed and managed by the child class. Creating instances of LocalStorageWriter makes no sense. Derive from it if you want to save some value to the local storage of the browser.