Help: add list of command signatures to top of INSTALL page

Help/command/install.rst

@@ -7,6 +7,14 @@ install
 
 Specify rules to run at install time.
 
+This command accepts several signatures:
+
+* :ref:`install(TARGETS) <install-targets>`
+* :ref:`install(FILES|PROGRAMS) <install-files>`
+* :ref:`install(DIRECTORY) <install-directory>`
+* :ref:`install(SCRIPT|CODE) <install-script>`
+* :ref:`install(EXPORT|EXPORT_ANDROID_MK) <install-export>`
+
 Introduction
 ^^^^^^^^^^^^
 
@@ -81,6 +89,8 @@ Command signatures that install files may print messages during
 installation.  Use the :variable:`CMAKE_INSTALL_MESSAGE` variable
 to control which messages are printed.
 
+.. _install-targets:
+
 Installing Targets
 ^^^^^^^^^^^^^^^^^^
 
@@ -197,6 +207,8 @@ The install destination given to the target install ``DESTINATION`` may
 use "generator expressions" with the syntax ``$<...>``.  See the
 :manual:`cmake-generator-expressions(7)` manual for available expressions.
 
+.. _install-files:
+
 Installing Files
 ^^^^^^^^^^^^^^^^
 
@@ -230,6 +242,8 @@ The install destination given to the files install ``DESTINATION`` may
 use "generator expressions" with the syntax ``$<...>``.  See the
 :manual:`cmake-generator-expressions(7)` manual for available expressions.
 
+.. _install-directory:
+
 Installing Directories
 ^^^^^^^^^^^^^^^^^^^^^^
 
@@ -311,6 +325,8 @@ given to the directory install ``DESTINATION`` may use "generator expressions"
 with the syntax ``$<...>``.  See the :manual:`cmake-generator-expressions(7)`
 manual for available expressions.
 
+.. _install-script:
+
 Custom Installation Logic
 ^^^^^^^^^^^^^^^^^^^^^^^^^
 
@@ -332,6 +348,8 @@ example, the code
 
 will print a message during installation.
 
+.. _install-export:
+
 Installing Exports
 ^^^^^^^^^^^^^^^^^^