Corrected file sorting mechanism

Files are now sorted by file name ascending by default. Case-insensitive comparison is now performed when sorting by file name or extension. When switching sorting fields ascending sorting will be used, otherwise sorting method will be toggled.
Fixed base URL calculation algorithm when HTTPS protocol is used
Merge pull request #111 from mpryvkin/feature1

Corrected file sorting mechanism
Merge pull request #112 from mpryvkin/feature2

Fixed base URL calculation algorithm when HTTPS protocol is used