Log Message:
Add lua-vstruct-2.1.1:

VStruct is a Lua library to provide functions for manipulating binary
data, in particular for reading binary files or byte buffers into Lua
values and for writing Lua values back into files or buffers. Supported
data types include:

- signed and unsigned integers of arbitrary size
- fixed and floating point numbers
- fixed-size, length-prefixed, and null-terminated strings
- booleans and bitmasks
- bit-packed integers, booleans and bitmasks

In addition, the library supports seeking, alignment, and byte order
controls, repetition, grouping of data into tables, and named fields.