Introduce nvim namespace: Move files.

Move files from src/ to src/nvim/.
- src/nvim/ becomes the new root dir for nvim executable sources.
- src/libnvim/ is planned to become root dir of the neovim library.

src/nvim/syntax_defs.h

@@ -0,0 +1,78 @@
+#ifndef NEOVIM_SYNTAX_DEFS_H
+#define NEOVIM_SYNTAX_DEFS_H
+
+#include "regexp_defs.h"
+
+/* struct passed to in_id_list() */
+struct sp_syn {
+  int inc_tag;                  /* ":syn include" unique tag */
+  short id;                     /* highlight group ID of item */
+  short       *cont_in_list;    /* cont.in group IDs, if non-zero */
+};
+
+/*
+ * Each keyword has one keyentry, which is linked in a hash list.
+ */
+typedef struct keyentry keyentry_T;
+
+struct keyentry {
+  keyentry_T  *ke_next;         /* next entry with identical "keyword[]" */
+  struct sp_syn k_syn;          /* struct passed to in_id_list() */
+  short       *next_list;       /* ID list for next match (if non-zero) */
+  int flags;
+  int k_char;                   /* conceal substitute character */
+  char_u keyword[1];            /* actually longer */
+};
+
+/*
+ * Struct used to store one state of the state stack.
+ */
+typedef struct buf_state {
+  int bs_idx;                    /* index of pattern */
+  int bs_flags;                  /* flags for pattern */
+  int bs_seqnr;                  /* stores si_seqnr */
+  int bs_cchar;                  /* stores si_cchar */
+  reg_extmatch_T *bs_extmatch;   /* external matches from start pattern */
+} bufstate_T;
+
+/*
+ * syn_state contains the syntax state stack for the start of one line.
+ * Used by b_sst_array[].
+ */
+typedef struct syn_state synstate_T;
+
+struct syn_state {
+  synstate_T  *sst_next;        /* next entry in used or free list */
+  linenr_T sst_lnum;            /* line number for this state */
+  union {
+    bufstate_T sst_stack[SST_FIX_STATES];          /* short state stack */
+    garray_T sst_ga;            /* growarray for long state stack */
+  } sst_union;
+  int sst_next_flags;           /* flags for sst_next_list */
+  int sst_stacksize;            /* number of states on the stack */
+  short       *sst_next_list;   /* "nextgroup" list in this state
+                                 * (this is a copy, don't free it! */
+  disptick_T sst_tick;          /* tick when last displayed */
+  linenr_T sst_change_lnum;     /* when non-zero, change in this line
+                                 * may have made the state invalid */
+};
+
+/*
+ * Structure shared between syntax.c, screen.c and gui_x11.c.
+ */
+typedef struct attr_entry {
+  short ae_attr;                        /* HL_BOLD, etc. */
+  union {
+    struct {
+      char_u          *start;           /* start escape sequence */
+      char_u          *stop;            /* stop escape sequence */
+    } term;
+    struct {
+      /* These colors need to be > 8 bits to hold 256. */
+      uint16_t fg_color;                /* foreground color number */
+      uint16_t bg_color;                /* background color number */
+    } cterm;
+  } ae_u;
+} attrentry_T;
+
+#endif // NEOVIM_SYNTAX_DEFS_H