Better documentation of :checksum and :checkout properties

* Explain the difference between :checkout and :checksum
* Document that hg method now supports these properties
document 719264d (even though it isn't merged yet)
Document that checksums may not be abbreviated

As requested in #626.
In hg, "checkout" is properly spelled "update"
Added pythonbrew-mini
smart-mode-line depends on dash
Merge pull request #1487 from dholm/bugfix/smart-mode-line

smart-mode-line depends on dash
New recipe for llvm-mode
New recipe for tablegen-mode
Merge pull request #1489 from dholm/recipe/llvm-mode

New recipe for llvm-mode
Merge pull request #1490 from dholm/recipe/tablegen-mode

Recipe/tablegen mode
New recipe for Verilog major mode
New recipe for VHDL major mode
Merge pull request #1492 from dholm/recipe/vhdl-mode

New recipe for VHDL major mode
Merge pull request #1491 from dholm/recipe/verilog-mode

New recipe for Verilog major mode
Correct decompression options for vhdl-mode
Merge pull request #1493 from dholm/bugfix/vhdl-mode

Correct decompression options for vhdl-mode
New recipe, outline-magic
Merge pull request #1495 from dholm/recipe/outline-magic

New recipe, outline-magic
Merge pull request #1488 from dougm/go

Go language related recipes and package installer