change INSTALL docs to use cmake

INSTALL.md

@@ -1,7 +1,7 @@
 This document provides generic information for compiling EncFS.
 
 If you are looking for specific instructions for your distribution,
-take a look at the page  
+take a look at the page
 **[Installing EncFS](https://github.com/vgough/encfs/wiki/Installing-Encfs)**
 in the wiki.
 
@@ -18,7 +18,7 @@ Steps to build EncFS:
     make
 
 Optional, but strongly recommended, is running the test suite
-to verfify that the generated binaries work as expected
+to verify that the generated binaries work as expected
 (runtime: 20 seconds)
 
     make test
@@ -29,8 +29,9 @@ the encfs directory.  You can install to in a system directory via
     make install
 
 . If the default path (`/usr/local`) is not where you want things
-installed, then use the `--prefix` option to `configure` to specify the
-install prefix.
+installed, then set the CMAKE_INSTALL_PREFIX option when running cmake.  Eg:
+
+    cmake .. -DCMAKE_INSTALL_PREFIX=/opt/local
 
 Encfs and encfsctl can also be installed by hand.  They need no special
 permissions.  You may also want the man pages encfs.1 and encfsctl.1.
@@ -45,10 +46,9 @@ EncFS depends on a number of libraries:
 Compiling on Debian and Ubuntu
 ==============================
 
-We use Travis CI to automatically build-test every commit:
+We use Drone.io to automatically build and test every commit.  See the README.md
+file for current build status.
 
-[![Build Status](https://travis-ci.org/vgough/encfs.svg)](https://travis-ci.org/vgough/encfs)
-
-The [Travis configuration file .travis.yml](.travis.yml) therefore
+The [Drone configuration file .drone.yml](.drone.yml) therefore
 always contains up-to-date instructions to build EncFS on Ubuntu
-(Travis uses Ubuntu build machines).
+(Drone is configured to use a Ubuntu build machines).