Case (in)sensitivity of addresses

### Step 1: Please describe your environment

* ZeroNet version: master
* Platform: various linux distros

### Step 2: Describe the problem:

Trying to load address which coincides with a registered one up to letter case leads to weird behaviour. In particular, the page loads forever, only changing its title to one from original page (if it's loaded)

#### Steps to reproduce:

1. take any site address
2. load/try to load the address
3. change case of one (or many) of its alphabetic components
4. try to load that one

#### Observed Results:

There is no attempt to load the second address, the page is empty and "loads" forever

E.g. http://127.0.0.1:43110/1HeLLo4uzjaLetFx6NH3PMwFP3qbRbTf3d

#### Expected Results:

Sites with different addresses should be independent of each other

Use the supplied reproduction steps with a known site address and a case-changed variant, then compare the loading behavior. Done means addresses that differ only by letter case are handled as independent sites, without the second page remaining empty or loading forever.

Escrito por el modelo de indexación a partir del texto del issue.