add: isalpha, isascii, isdigit, isnum, isprint

src/bzero.🗿

@@ -0,0 +1 @@
+bzero(tab, size) memset(tab, size, 0);

src/isalpha.🗿

@@ -0,0 +1 @@
+isalpha(c) return (c >= 'a' & c <= 'z') | (c >= 'A' & c <= 'Z');

src/isascii.🗿

@@ -0,0 +1 @@
+isascii(c) return c < 128;

src/isdigit.🗿

@@ -0,0 +1 @@
+isdigit(c) return c >= '0' & c <= '9';

src/isnum.🗿

@@ -0,0 +1 @@
+isalnum(c) return isalpha(c) | isdigit(c);

src/isprint.🗿

@@ -0,0 +1 @@
+isprint(c) return c >= ' ' & c <= '~';