Migrated integer usage to stdint.h types.

Details:
- Changed the way bli_type_defs.h defines integer types so that dim_t,
  inc_t, doff_t, etc. are all defined in terms of gint_t (general signed
  integer) or guint_t (general unsigned integer).
- Renamed Fortran types fchar and fint to f77_char and f77_int.
- Define f77_int as int64_t if a new configuration variable,
  BLIS_ENABLE_BLIS2BLAS_INT64, is defined, and int32_t otherwise.
  These types are defined in stdint.h, which is now included in blis.h.
- Renamed "complex" type in f2c files to "singlecomplex" and typedef'ed
  in terms of scomplex.
- Renamed "char" type in f2c files to "character" and typedef'ed in terms
  of char.
- Updated bla_amax() wrappers so that the return type is defined directly
  as f77_int, rather than letting the prototype-generating macro decide
  the type. This was the only use of GENTFUNC2I/GENTPROT2I-related macros,
  so I removed them. Also, changed the body of the wrapper so that a
  gint_t is passed into abmaxv, which is THEN typecast to an f77_int
  before returning the value.
- Updated f2c code that accessed .r and .i fields of complex and
  doublecomplex types so that they use .real and .imag instead (now that
  we are using scomplex and dcomplex).

frame/compat/bla_her2k.c

@@ -42,15 +42,15 @@
 #define GENTFUNCCO( ftype, ftype_r, ch, chr, blasname, blisname ) \
 \
 void PASTEF77(ch,blasname)( \
-                            fchar*    uploc, \
-                            fchar*    transa, \
-                            fint*     m, \
-                            fint*     k, \
+                            f77_char* uploc, \
+                            f77_char* transa, \
+                            f77_int*  m, \
+                            f77_int*  k, \
                             ftype*    alpha, \
-                            ftype*    a, fint* lda, \
-                            ftype*    b, fint* ldb, \
+                            ftype*    a, f77_int* lda, \
+                            ftype*    b, f77_int* ldb, \
                             ftype_r*  beta, \
-                            ftype*    c, fint* ldc  \
+                            ftype*    c, f77_int* ldc  \
                           ) \
 { \
 	uplo_t  blis_uploc; \