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, 37 deletions

diff --git a/lexers/man.lua b/lexers/man.lua
deleted file mode 100644
index 557e11d..0000000
--- a/lexers/man.lua
+++ /dev/null
@@ -1,37 +0,0 @@
--- Copyright 2015-2016 David B. Lamkins <david@lamkins.net>. See LICENSE.
--- man/roff 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 = 'man'}
-
--- Whitespace.
-local ws = token(l.WHITESPACE, l.space^1)
-
--- Markup.
-local rule1 = token(l.STRING,
-                    P('.') * (P('B') * P('R')^-1 + P('I') * P('PR')^-1) *
-                    l.nonnewline^0)
-local rule2 = token(l.NUMBER, P('.') * S('ST') * P('H') * l.nonnewline^0)
-local rule3 = token(l.KEYWORD,
-                    P('.br') + P('.DS') + P('.RS') + P('.RE') + P('.PD'))
-local rule4 = token(l.LABEL, P('.') * (S('ST') * P('H') + P('.TP')))
-local rule5 = token(l.VARIABLE,
-                    P('.B') * P('R')^-1 + P('.I') * S('PR')^-1 + P('.PP'))
-local rule6 = token(l.TYPE, P('\\f') * S('BIPR'))
-local rule7 = token(l.PREPROCESSOR, l.starts_line('.') * l.alpha^1)
-
-M._rules = {
-  {'whitespace', ws},
-  {'rule1', rule1},
-  {'rule2', rule2},
-  {'rule3', rule3},
-  {'rule4', rule4},
-  {'rule5', rule5},
-  {'rule6', rule6},
-  {'rule7', rule7},
-}
-
-return M