* Updated usbSendCommand() to make it send the command header first, and then the command block. Makes it easier for host applications to read and parse command data.
* Let usbSendCommand() take care of handling ZLT packets if required by any command block (only SendNspHeader at this moment), as well as logging status data via usbLogStatusDetail().
* Updated USB ABI specs doc.
* gamecard: added more comments, modified gamecardGetBundledFirmwareUpdateVersion() to fill a VersionType1 pointer instead of a u32, fallback to manually reading the gamecard certificate if fsDeviceOperatorGetGameCardDeviceCertificate() fails, updated GameCardFwVersion enum.
* title: tweaked conditions for some functions.
* usb: explicitly defined values for previously omitted struct members while initializing USB comms, imported libusb structs to make it easier to work with the USB BOS, added a few more comments and changed around some code.
* utils: tweaked the illegal filesystem character array to remove some chars that are actually allowed.
Key area and certificate can be optionally appended and/or preserved, respectively. Trimming is supported.
Also added a bunch of ZLT packet related fixes to usb.c, as well as a function to properly cancel an ongoing file transfer.
* Codestyle fixes.
* NCA contexts for NCAs with titlekey crypto will now be generated even if the ticket can't be retrieved, in order to be able to use ncaReadContentFile() with them.
* Moved aes128XtsNintendoCrypt() out of nca.c.
* Updated disclaimer in all source files.
* Improved signed payload (certificate, ticket) handling.
* Prefer strlen + strcmp over strncmp whenever possible.
* Simplify header file inclusions in source files.
* Simplify background gamecard thread logic.
* Properly close keys file handle if there's a key parse error.
* Update NcaKeyGeneration enum.
* Small changes to save.c/h.
Will probably have to revert some USB changes...