feat: add most gr scalar operations and fmpzi

Author: oscarbenjamin

src/flint/__init__.py

@@ -1,6 +1,6 @@
 from .pyflint import *
 
-from .types.gr import gr_ctx, gr_fmpz_ctx, gr_fmpq_ctx
+from .types.gr import gr_ctx, gr_fmpz_ctx, gr_fmpq_ctx, gr_fmpzi_ctx
 
 from .types.fmpz import *
 from .types.fmpz_poly import *

src/flint/flintlib/types/gr.pxd

@@ -8,12 +8,10 @@ from flint.flintlib.types.flint cimport (
 
 cdef extern from "flint/gr.h":
 
-    cdef enum truth_t_enum:
-        T_TRUE
-        T_FALSE
-        T_UNKNOWN
-
-    ctypedef truth_t_enum truth_t
+    ctypedef int truth_t
+    cdef int T_TRUE
+    cdef int T_FALSE
+    cdef int T_UNKNOWN
 
     # Macros
     cdef int GR_SUCCESS