Support GAS syntax

[13xforever]

This was one of the most requested features. Current docs are here.
Relevant branch: sublime-syntax

• Syntax
  • Preprocessing
  • Whitespace
  • Comments
  • Symbols
  • Statements
  • Constants
    • Character Constants
    • Number Constants
• Sections and Relocation
  • Background
  • Linker Sections
  • Assembler Internal Sections
  • Sub-Sections
  • bss Section
• Symbols
  • Labels
  • Giving Symbols Other Values
  • Symbol Names
  • The Special Dot Symbol
  • Symbol Attributes
    • Value
    • Type
    • Symbol Attributes: a.out
    • Symbol Attributes for COFF
    • Symbol Attributes for SOM
• Expressions
  • Empty Expressions
  • Integer Expressions
    • Arguments
    • Operators
    • Prefix Operator
    • Infix Operators
• Assembler Directives
  • .abort
  • .ABORT (COFF)
  • .align abs-expr, abs-expr, abs-expr
  • .altmacro
  • .ascii "string"…
  • .asciz "string"…
  • .balign[wl] abs-expr, abs-expr, abs-expr
  • Bundle directives
  • .byte expressions
  • CFI directives
  • .comm symbol , length
  • .data subsection
  • .def name
  • .desc symbol, abs-expression
  • .dim
  • .double flonums
  • .eject
  • .else
  • .elseif
  • .end
  • .endef
  • .endfunc
  • .endif
  • .equ symbol, expression
  • .equiv symbol, expression
  • .eqv symbol, expression
  • .err
  • .error "string"
  • .exitm
  • .extern
  • .fail expression
  • .file
  • .fill repeat , size , value
  • .float flonums
  • .func name[,label]
  • .global symbol, .globl symbol
  • .gnu_attribute tag,value
  • .hidden names
  • .hword expressions
  • .ident
  • .if absolute expression
  • .incbin "file"[,skip[,count]]
  • .include "file"
  • .int expressions
  • .internal names
  • .irp symbol,values…
  • .irpc symbol,values…
  • .lcomm symbol , length
  • .lflags
  • .line line-number
  • .linkonce [type]
  • .list
  • .ln line-number
  • .loc fileno lineno [column] [options]
  • .loc_mark_labels enable
  • .local names
  • .long expressions
  • .macro
  • .mri val
  • .noaltmacro
  • .nolist
  • .octa bignums
  • .offset loc
  • .org new-lc , fill
  • .p2align[wl] abs-expr, abs-expr, abs-expr
  • .popsection
  • .previous
  • .print string
  • .protected names
  • .psize lines , columns
  • .purgem name
  • .pushsection name [, subsection] [, "flags"[, @type[,arguments]]]
  • .quad bignums
  • .reloc offset, reloc_name[, expression]
  • .rept count
  • .sbttl "subheading"
  • .scl class
  • .section name
  • .set symbol, expression
  • .short expressions
  • .single flonums
  • .size
  • .skip size , fill
  • .sleb128 expressions
  • .space size , fill
  • .stabd, .stabn, .stabs
  • .string "str", .string8 "str", .string16
  • .struct expression
  • .subsection name
  • .symver
  • .tag structname
  • .text subsection
  • .title "heading"
  • .type
  • .uleb128 expressions
  • .val addr
  • .version "string"
  • .vtable_entry table, offset
  • .vtable_inherit child, parent
  • .warning "string"
  • .weak names
  • .weakref alias, target
  • .word expressions
  • .zero size
  • .2byte expression [, expression]*
  • .4byte expression [, expression]*
  • .8byte expression [, expression]*
  • Deprecated Directives
• Object Attributes
  • GNU Object Attributes
  • Defining New Object Attributes
• Machine Dependent Features
  • 80386 Dependent Features
    • Options
    • x86 specific Directives
    • i386 Syntactical Considerations
    • i386-Mnemonics
    • Register Naming
    • Instruction Prefixes
    • Memory References
    • Handling of Jump Instructions
    • Floating Point
    • Intel’s MMX and AMD’s 3DNow! SIMD Operations
    • AMD’s Lightweight Profiling Instructions
    • Bit Manipulation Instructions
    • AMD’s Trailing Bit Manipulation Instructions
    • Writing 16-bit Code
    • Specifying CPU Architecture
    • AT&T Syntax bugs
    • Notes
  • IA-64 Dependent Features
    • Options
    • Syntax
      • Special Characters
      • Register Names
      • IA-64 Processor-Status-Register (PSR) Bit Names
      • Relocations
    • Opcodes