Add new topics to TOC

Author: Colin Robertson

docs/standard-library/TOC.md

@@ -440,6 +440,7 @@
 #### [extent Class](extent-class.md)
 #### [integer_sequence Class](integer-sequence-class.md)
 #### [integral_constant Class, bool_constant Class](integral-constant-class-bool-constant-class.md)
+#### [invoke_result Class](invoke-result-class.md)
 #### [is_abstract Class](is-abstract-class.md)
 #### [is_arithmetic Class](is-arithmetic-class.md)
 #### [is_array Class](is-array-class.md)
@@ -461,6 +462,7 @@
 #### [is_function Class](is-function-class.md)
 #### [is_fundamental Class](is-fundamental-class.md)
 #### [is_integral Class](is-integral-class.md)
+#### [is_invocable classes](is-invocable-classes.md)
 #### [is_literal_type Class](is-literal-type-class.md)
 #### [is_lvalue_reference Class](is-lvalue-reference-class.md)
 #### [is_member_function_pointer Class](is-member-function-pointer-class.md)