Move all lua related files to lua/ subfolder

Also remove the lexers sub directory from the Lua search path.
As a result we attempt to open fewer files during startup:

 $ strace -e open -o log ./vis +q config.h && wc -l log

In order to avoid having to modifiy all lexers which `require('lexer')`
we instead place a symlink in the top level directory.

 $ ./configure --disable-lua
 $ rm -rf lua

Should result in a source tree with most lua specifc functionality
removed.

1 files changed, 0 insertions, 55 deletions

diff --git a/lexers/dockerfile.lua b/lexers/dockerfile.lua
deleted file mode 100644
index 3f6ca7f..0000000
--- a/lexers/dockerfile.lua
+++ /dev/null
@@ -1,55 +0,0 @@
--- Copyright 2016 Alejandro Baez (https://keybase.io/baez). See LICENSE.
--- Dockerfile LPeg lexer.
-
-local l = require('lexer')
-local token, word_match = l.token, l.word_match
-local P, R, S = lpeg.P, lpeg.R, lpeg.S
-
-local M = {_NAME = 'dockerfile'}
-
--- Whitespace
-local indent = #l.starts_line(S(' \t')) *
-               (token(l.WHITESPACE, ' ') + token('indent_error', '\t'))^1
-local ws = token(l.WHITESPACE, S(' \t')^1 + l.newline^1)
-
--- Comments.
-local comment = token(l.COMMENT, '#' * l.nonnewline^0)
-
--- Strings.
-local sq_str = l.delimited_range("'", false, true)
-local dq_str = l.delimited_range('"')
-local string = token(l.STRING, sq_str + dq_str)
-
--- Numbers.
-local number = token(l.NUMBER, l.float + l.integer)
-
--- Keywords.
-local keyword = token(l.KEYWORD, word_match{
-  'ADD', 'ARG', 'CMD', 'COPY', 'ENTRYPOINT', 'ENV', 'EXPOSE', 'FROM', 'LABEL',
-  'MAINTAINER', 'ONBUILD', 'RUN', 'STOPSIGNAL', 'USER', 'VOLUME', 'WORKDIR'
-})
-
--- Identifiers.
-local identifier = token(l.IDENTIFIER, l.word)
-
--- Variable.
-local variable = token(l.VARIABLE,
-                       S('$')^1 * (S('{')^1 * l.word * S('}')^1 + l.word))
-
--- Operators.
-local operator = token(l.OPERATOR, S('\\[],=:{}'))
-
-M._rules = {
-  {'whitespace', ws},
-  {'keyword', keyword},
-  {'variable', variable},
-  {'identifier', identifier},
-  {'string', string},
-  {'comment', comment},
-  {'number', number},
-  {'operator', operator},
-}
-
-M._FOLDBYINDENTATION = true
-
-return M